12 points

Bezel with 12 diamonds. One on each index.Bisel con 12 diamantes. Uno en cada índice.

2 lines - 4 lines

Number of lines of text on the dial, usually from the submariner model (e.g. 14060 or 5512-5513).

24 diamants

Smooth bezel with 12 large and 12 small diamonds set.

904L steel

Special steel alloy that Rolex uses for its watches. It is very dense and strong. Rolex is the ONLY watch company to use this special steel.



Argentine Air Force.

Acrylic glass

The previous generation material used on Rolex crystals was acrylic, a plastic-like material. The advantage is that it can be polished.


Any part of a watch that is not original, i.e. that does not exist in the brand’s official catalogue.


Refers to a version of the 6263 (white dial) for which the sub-dials are also white.

Albino Freccione

Vintage Rolex Explorer 1655 whose orange GMT hand has turned white over time.


An essential accessory for aviators, an altimeter measures altitude, or the height above sea level. Recording ascents and descents, an altimeter can also be important equipment for climbers, hikers, mountaineers and other professionals for whom altitude is a necessary measurement.

AM/PM indicator

A function that indicates whether the time shown is AM or PM. This function is mainly (but not exclusively) found in watches with a GMT/Double time display or a world time display, in order to know whether it is day or night in other time zones.

Analog/Digital (Duo) display

A dial or face of a watch that has the ability to display the time using rotating hands or other markers on a dial, (an analog display) and electronically by digital units (a digital display) on the dial simultaneously. This is also known as a duo display or AnaDigi watch.


A watch that uses rotating hands or other markers on a dial to indicate the time.


The anchor has a dual role: on the one hand, it transmits the force of the spring through the gear train to the balance wheel in order to maintain the oscillations, and on the other hand, it prevents the uncontrolled unwinding of the wound gear train.

Annual Calendar

A complication indicating the date, day and month. An extremely complicated and sought-after movement. This watch adjusts correctly to the short and long months, but it does not take into account the leap year, i.e. the 29 days in February every four years.

Anodised aluminium

Material with which the bezel inserts of Submariners and GMTs were made before the current Cerachrome.


Type of dial where the hour markers are Arabic numerals (1, 2, 3, etc.)

Argentinian bracelet

For some time, some “president’s bracelets” were made in Argentina with stylistic modifications to the buckle.


Type of watch hands and hour markers – found only on antique pieces – in the shape of an arrow.


Designates the characteristic bezel of the Rolex Zephyr.

Automatic countdown repetition

A countdown timer that resets when the preset time has elapsed and repeats / restarts. The countdown cycle runs continuously until the stop button is pressed.



Plastic material of which certain Vintage Rolex inserts (GMT Master and Daytona) are made.

Balance Cock

A separate bridge containing the balance and regulator assemblies.

Balance Spring

Also known as a hair spring, this is a very thin spring in a mechanical watch that causes the balance wheel to recoil. Its length and adjustment allow the timing of the watch to be set.

Balance wheel

The balance wheel and hairspring move back and forth. Each of these back and forth movements (“ticking”) is called an oscillation. It is a weighted wheel in a mechanical movement that rotates back and forth separating time into beats. It is an essential mechanism for the accuracy of time in a watch.

Barb Buckle

A buckle is a standard fastening system for watch straps, similar to a belt for the waist. The pin is the small piece of metal that is inserted into one of the holes in a leather watch band to secure the buckle. Simple and precise!


Refers to the “bark” finish of the bezels and central links of certain Day Dates.


A special finish applied to some of the President’s bracelets and spectacles – the gold is “etched” to resemble tree bark – not currently used by Rolex.


A covered cylindrical case with gear teeth on the outside that houses the mainspring in a mechanical watch. The size of the barrel determines the length of the power reserve or stored energy of a mechanical movement. The teeth surrounding the barrel drive the wheel train.

Bart Simpson

The Bart Simpson dial designates the crushed Rolex logo crown, reminiscent of the famous character’s hairstyle (1965).


The nickname of the GMT-Master II ref. 126710BLNR refers to the black and blue Cerachrom ceramic bezel of the watch.


The nickname of the GMT-Master II ref. 116710BLNR refers to the black and blue Cerachrom ceramic bezel of the watch.


A type of dial found on some gold Daytonas. It can be pink, green, blue etc.

Bertolli Bezel

Defined for Italian collectors the olive green of the 16610 LV inserts, in reference to the colour of the olive oil of this famous brand.


The angled corner on some older style professional fashion cases, often erased by multiple polishings, desirable in the collectors’ market.


English Rolex Centre (specialising in military Rolexes). Its trademark is a polishing with very marked bevels.


A ring on the top of the case surrounding the crystal. It can be decorative or functional. The bezel can be fixed, move in one direction (unidirectional) or in both directions (bidirectional). Many functional bezels allow the time to be calibrated from a given point by rotating the position of the bezel relative to a given starting reference point along the dial.The metal ring on the outside of the glass. Over the years, Rolex has used a variety of materials to make its bezels. The most common materials used for Rolex glasses are steel and their patented Cerachrom material. Other materials commonly used by Rolex for their eyewear include bakelite and aluminium.

Bezel insert

On some professional models, the bezel has a removable insert to indicate different functions, e.g. elapsed time, 24 hours, etc.

Bezel with 24 diamonds

Smooth bezel with 12 large and 12 small diamonds set.

Bi Directional Bezel

A bezel that can be moved both clockwise and counter-clockwise to perform mathematical functions using the watch face as a reference. A bi-directional bezel is similar to a slide rule and is extremely useful for aviators and aviator watches.


Term mainly used by transalpine merchants for lacquered dials, ringed indexes and often with a cream or “fresh butter” patina.

Big Crown

Reference to the large crown. For example the Submariner worn by James Bond in Dr No. The crown is 8mm without shoulder and is engraved “BREVET”. (References: 6200, 6538, 6540, 5510).

Big Eyes

Refers to the sub-dials on some Daytonas. They are bigger. As a result, they look like big eyes.

Big number

Refers to the 3rd series of 5514. It was produced exclusively for the Comex. The diver numbers (above 700) are larger. The engraving “ROLEX COMEX” is in a circle, separated by two ROLEX crowns. Serial number between 4 and 5,5 Million (1976 / 1978).

Big Red

Daytona reference 6263. The Daytona is marked in red.

Black Out

Dial of Explorer 1 reference 14270 with black inside 3/6/9 indexes.


The 2 central parts of the butterfly clasp.


Designates the AirKing presented at Basel 2016. Rolex clearly takes its cues from the measuring instruments of the Bloodhound SSC hypersonic land vehicle that will attempt to break the world speed record. The OPC is the first to have named it so.


Designates the GMT Master with an all-blue insert.

Bombay lugs

Type of lugs stylised on vintage Datejust, characterised by the lugs rising to a point in the centre. It refers to several references such as the 5016 or 5018. Bombay comes from “bombé” which refers to the particular shape of the case.

Bottom of the box

The back of the watch case which can be opened to access the watch movement for repair or battery change. Some watches have a sapphire crystal case back which allows the working mechanism of the watch to be seen.

Box & Papers

A term referring to the original watch box and the original documents or warranty card given to the original owner upon initial purchase from the jeweller. Collectors like to have the “box and documents” to make their watch a complete set.

Breguet Spring

The balance spring on which the balance wheel is balanced tends to settle on opposite sides when it expands or contracts. The constant displacement of their gravity disturbs the movement of the balance wheel. Breguet solved the problem in 1795 by raising the last coil of the spring and giving it a smaller curve. This Breguet surge encourages the spring to expand concentrically, improving the running of the watch and reducing wear on the balance pivots.


A metal movement part which is attached to a base plate and holds at least one bearing of a rotating part.

Broad Arrow

Refers to the British Army endowment watches. An arrow is engraved on the case back of these watches.


Bronze is an alloy of copper and arsenic that reacts with oxygen (= oxidation). A natural patina forms, which darkens the bronze and gives each watch its individual character. Oxidation of bronze is a natural process and not a quality defect. In order to keep the oxidation of the bronze components of a DAVOSA watch to a minimum before it is worn by the buyer, the watch is delivered in a protective vacuum bag. We recommend keeping the watch in this case before wearing it. When the watch has been unwrapped, the bronze parts should not come into contact with the skin to avoid locally increased discolouration of the surface. Bronze watches should be stored in a cool, dry and dark place. We recommend not to remove the patina. It acts as a natural protective layer for the bronze. You can clean the bronze parts carefully to remove unsightly marks: We recommend mixing salt with a little vinegar and scrubbing with a soft brush, then rinsing with water.


A type of polishing used on stainless steel and gold watches. The surface is “brushed” to give the pieces a flat and sleek finish.


Vintage case style from the 1930s-50s with a distinctly domed case back to accommodate the winding rotor. The particularly domed models were given the nickname “Ovettone”, which literally means “big egg” in Italian.


Named after the famous New York salesman. These are dials with painted Roman indexes.

Bulls Eye

Refers to Rolex dials with a circle in the centre.


Service dials for 6538 “military”. It has the 3-6-9 dial.

Butterfly (Cal.)

This refers to calibres whose rotor is not a complete half disc, it has a butterfly shape. (1030, 1530, 1560, 1565…)


"Coke" bezel

Refers to the black and red bezel found on some models of the Rolex GMT-Master II watch.


A function that shows the date, and often the day of the week and month. Most calendar watches display the information digitally through an aperture on the watch face. If the watches have a perpetual calendar, this means that the date changes automatically at the end of the month. Some chronograph watches display the information on sub-dials on the watch face.


Originally a synonym for “size” to describe a watch movement, “calibre” now refers to the movement itself. Followed by a series of numbers and letters, the calibre indicates the origin of the movement, its reference and the name of the manufacturer. Some brands make their own calibre, called a “manufacture calibre”. However, many watches today are made with ETA calibres (generic, mass-produced, highly reliable movements).


One part of the dial is in Roman numerals, the other in Arabic numerals.


It is a domed/arched crystal.


Discontinued bezel – only 18k – “Rolex” printed at position 6


The case of a watch is the main housing of the internal movement of the watch.


Range of Rolex watches, in its first non-waterproof, non-automatic, manual or quartz versions.


Refers to the ceramic composite material used in the modern GMT, Submariner and Daytona bezels.

Cerachrom bezel

Unveiled in 2005, Cerachrom is Rolex’s patented approach to a high-tech ceramic bezel. The word “Cerachom” is a compound word combining the words “ceramic” and “chrom”, the ancient Greek word for colour. Prized for its resistance to both fading and scratching, the majority of Rolex sports watches are now equipped with a Cerachrom bezel.


A chamfer is a transition edge between two faces of an object. Sometimes defined as a bevel shape, it is often created at a 45° angle between two adjacent faces at right angles.

Chapter Ring

A border running around the dial integrating the minute markers.


Chromalight is the luminescent material used by Rolex on the dial and sometimes the bezel of some of its current watches. It glows blue in the dark rather than the usual green and lasts up to eight hours. It made its debut in 2008 on the new DeepSea Sea Dweller and has since made its way onto other Rolex watches.

Chronergy Escapement

The escapement is a major component of a mechanical movement. It takes energy from the wound mainspring and distributes it in small, controlled increments to the rest of the movement, which in turn produces the familiar ticking sound. In 2015, Rolex introduced its patented Chronergy escapement in the new calibre 3255. The increased efficiency of the Chronergy escapement has given way to an increase in power reserve.


Not to be confused with Chronometer which certifies precision (see COSC). The chronograph (like the Daytona) is used to measure short times and can be recognised by the additional counters on the dial and the push buttons on the side of the case.


Technically, all watches are chronometers. But for a Swiss-made watch to qualify as a chronometer, it must meet certain very strict standards set by the Contrôle officiel suisse des chronomètres (C.O.S.C.). If you have a Swiss watch labelled as a chronometer, you can be sure that it is equipped with a very high quality mechanical movement, which has undergone a series of precision tests at an official institute. The requirements are very strict: a few seconds per day in the most unfavourable temperature conditions (for mechanical watches) and positions that are usually encountered. A chronometer is a high-precision watch that displays seconds and whose movement has been tested and certified by an independent body, the COSC. A chronograph can only be called a chronometer if it has been certified by this official body.

Circled indexes

A type of white gold circled index that appeared around 84-85.

Clockmaker's Four

The fact of writing IIII and not IV on the dials with Roman numerals for the index indicating the 4. The IV only appeared in the Middle Ages (IV being the initial of the God IVPITER). The first clocks therefore used the IIII. For historical and even aesthetic reasons, many brands still use the IIII. Rolex is no exception to the rule!


Only used on French forums (do not use on American forums). The term designates the GMT Master of transition with the 3186 movement. A killer according to some, hence the nickname. Concerns the end of the “Z” series and the “M” series.


It is a company specialising in engineering and the underwater world. Comex is the abbreviation of “Compagnie Maritime d’Expertises”. Rolex has produced Submariner and SD watches for COMEX.

Comex Toothpaste

Refers to the luminescent paste used on the dials of some COMEX watches in the 1990s and some other watches. It is a dense and compact mixture that resembles Tritium but whose formula is not known.


Based on Oyster Precision with explorer dial type 3/6/9 and commando flocking – produced for the US market only (manual winding).


One or more features added to a watch in addition to its usual timekeeping functions, which normally include not only the hours, minutes and seconds, but also the date and often the day of the week. Complications such as perpetual calendars, moon phases, alarms, repeater mechanisms, quarter chimes and stop/start chronograph functions are also included. Power reserve indicators are also generally considered as “complications”.


Nickname given to some GMT Master 1675 full gold with brown dial called “nipple dial” and equipped with stick hands and not with their usual Mercedes hands. This nickname can also be applied to designate the type of hands which equip this GMT which appeared in an advertisement featuring the Concorde.


The COSC, or Contrôle Officiel Suisse des Chronomètres, is an organisation that grants the title of chronometer to watches sent in for approval by watch manufacturers. Certification is granted for each individual movement. Each movement undergoes a number of tests to verify its reliability and accuracy in different situations with temperature variations. This certification is a true assurance of quality and craftsmanship.


“The name comes from the reference 6062 Oyster Perpetual with moon phases and triple date, produced from 1950 to 1953. It was called Cosmograph because of the moon phases shown on a blue starry sky background. This name was taken over in 1963 to designate the new chronograph in reference to the space conquests of the late 1950s. Introduced in 1963, the Cosmograph was Rolex’s new generation of chronograph watches. Although Cosmograph is Rolex’s official name for its chronograph watches, today this family of famous luxury sports watches is known simply as Daytona. “

Côtes de Genève

A form of decoration in high-quality watch movements that resembles a pattern on the watch face.

Countdown timer

A function that allows the user to know how much time has elapsed during a predefined period. Some countdown timers give a warning signal a few seconds before the time runs out. They are useful in events such as yacht races, where the sailor has to manoeuvre the boat into position before the race starts.


Refers to the cross on some dials. It represents a reticule (crossing of wires that define the axis of sight of an optical instrument).


The crown of the winding mechanism is a button that allows us to wind a watch and set the time, day and date. Some crowns, such as those for diving watches, are screwed down to ensure the watch is water resistant. Sometimes the crown of the winding mechanism is also a pusher that triggers the chronograph.

Crystal / Glass

The cover that covers the watch face is called the crystal (or glass). There are three types of crystal commonly used in watches: Acrylic crystal is a cheap plastic that can polish out shallow scratches. Mineral crystal is made up of several elements that are heat treated to create an unusual hardness that helps resist scratching. Sapphire crystal is the most expensive and durable, about three times harder than mineral crystal and 20 times harder than acrylic crystal. A non-reflective coating on some sports models prevents glare.


The cyclops is a convex magnifying glass applied directly to the watch glass. It facilitates the reading of the date by magnifying it 2.5 times.


Dark Rhodium

Refers to the dark grey sunray dials found on the Oyster Perpetual, Datejust or Yacht-Master in particular.


Refers to the dark grey sunray dials found on the Oyster Perpetual, Datejust or Yacht-Master in particular.


The quintessential Rolex watch. This is the model most people think of when they hear the word Rolex. The name is derived from its function: the Datejust face displays the day of the month in a small window on the right side of the dial.

Dato Compax / Killy

Refers to references 4767, 4768, 5036, 6036 and 6236. Pre-daytona with day/month indication in addition to the chronograph.

David Bowie

Refers to the different coloured patinas on the indexes according to their shape. This feature can be found on 1675s. It reminds us of the singer’s eyes, which had the particularity of being different.

Day / Night

A watch that shows both the day of the week and the date of the month.

Day / Night indicator

A function that indicates whether the time shown is AM or PM. This function is mainly (but not exclusively) found in watches with a GMT/Double time display or a world time display, in order to know whether it is day or night in other time zones.

Daytona 13

Gold model (16528) on which the 15 minute index has been replaced by mistake (on the strength of an apology letter from Mr HEINIGER, former CEO of the brand) by a 13. In 2011, one of them sold for 100 000€ in Geneva.

Deep Sea

Rolex professional watches and current diving watches can be immersed much deeper than a Submariner


The main metal part of the watch that displays all the information (hours, minutes and seconds) through the hands and indexes on it. The dials come in a variety of beautiful colours, as well as engraved, embossed, ribbed and guilloche patterns.

Diamond bezels

A generic term for any bezel with diamonds. It is most commonly seen on the Datejust and Day-Date models of Rolex watches.

Diamond dial

This term is used to refer to any dial that has diamond markers instead of dot markers or other types of standard markers.

Dirty Harry

Another name for the GMT-Master ref. 1675 in the “Root Beer” colour scheme. 1675, famously worn by Clint Eastwood, even though his most famous character wore a Timex when he blew up the bad guys. This 1970 example was estimated at $4,000-$6,000 at Antiquorum in 2016.

Diving watch

A watch that withstands at least 200 metres underwater. A diver’s watch has a unidirectional rotating bezel and a screw-down crown and caseback. Some watches have a helium release button to release the pressure after diving.

DLC (Diamond Like Carbon)

DLC (Diamond Like Carbon) is a coating that significantly darkens the stainless steel of a watch. It is an alloy that combines carbon and diamond for maximum strength. Thanks to ionisation coating, a process used in Formula 1 and aerospace, this indestructible coating has been applied to watches.

Doctor (the)

Refers to 3 examples of 6239 which have a dial with an additional scale.

Door Stop Dial

Refers to dials with large raised indexes at 6 and 9 o’clock. They look like door blocks.

Double Red

Designates the Sea-Dweller 1665 with two lines of red literature on the dial.

Double Silver

5508 dial with depth and submariner indications in white.

Double Swiss

Double Swiss writing on the dial.

Dress Explorer

This refers to the vintage “Explorer” with mainly white dial (steel or gold) without the classic explorer dial but with the applied indexes.

Dual Display

A display that shows the time by both the hour and minute hands (an analogue display) and by digits (a digital display). It is also known as the AnaDigi display.

Dual Time

A watch that shows the local time and the time in at least one other time zone. This is usually displayed by an additional hour hand that tracks the time in the 24-hour mode. Some watches have a separate sub-dial showing the full time of the additional time zone.


Eagle Beak

Crown guard in the shape of an eagle’s beak.


The patented Easylink extension system allows the wearer to extend the length of an Oyster bracelet by 5 mm without the need for tools.

Elapsed Time Rotating Bezel

Une lunette rotative graduée utilisée pour garder la trace des périodes de temps. La lunette peut être tournée afin que le porteur puisse aligner le zéro de la lunette avec l’aiguille des secondes ou des minutes de la montre. Vous pouvez alors lire le temps écoulé sur la lunette. Cela évite d’avoir à effectuer la soustraction qui serait nécessaire si vous utilisiez le cadran normal de la montre.


Designates enamelled dials.

End Link

Metal addition surrounding the pump, making the link between the bracelet and the box.

End of battery/cell life (EOL) indicator

The EOL indicates when it is time to replace the existing battery. Manufacturers use different methods to indicate low battery. For example, if a second hand usually sweeps, when the battery is low it starts to tinkle.

Engine Turning/Turned

It is a centuries-old craft that still involves the use of ancient machines to engrave delicate designs on the metal components of watches, including cases, dials, bezels and movements. It is also known as guilloche.

Engraved top

The flange is the part that joins the dial to the glass. At Rolex, the flange is engraved ROLEXROLEXROLEXROLEX…. on recent models.


End of life. In a quartz movement, the end of battery life is indicated by the second hand, which starts jumping every four seconds. The battery must be changed immediately.

Equation Of Time (EOT)

A complication of the equation of time (a.k.a. EOT) indicates the difference between “true” solar time (that of nature) and “mean” solar time (that of man). As the earth revolves around the sun in an elliptical (oval) shape and the axis is tilted, there are only 4 days per year when the day lasts exactly 24 hours: 15 April, 14 June, 1 September and 24 December. On all other days of the year, the days are shorter or longer, depending on the position of the earth. This watch will show the difference between the “average” time and the “true” time. Since the number of days is fixed year after year (in the same place), a watch can be made to reproduce the correction via a shaped cam that lengthens or shortens the days accordingly.


The device at the heart of virtually all timekeeping mechanisms. The mechanism that “releases” the energy that sustains the oscillations of the balance wheel, which governs the speed at which the escapement turns the wheels and hands of the watch. The set of parts (escapement wheel, lever, roller) that transforms the rotary motion of the train into a back-and-forth motion (the balance wheel).


An alloy created by Rolex that is similar to rose gold. Although the composition is not communicated by Rolex, it could be 76% gold, 22% copper and 2% titanium. Chemically, titanium is a stable material. As a result, Everose is said to be more durable than classic rose gold.

Exclamation mark

Refers to the point below the 6 o’clock index.

Exhaust lever

The lever splits into two pallets which lock and unlock the escapement wheel teeth. The action is governed by the balance wheel which engages the other end of the lever, the escapement teeth sliding over the inclined pallets live the lever to give the balance wheel a push.

Explorer dial

Refers to the 3-6-9 dial on the Submariner 6200 or Explorer 1 (14270, 114270).



Refers to Rolex inserts that are faded, weathered or artificially aged.

Fat Font

Refers to the bold writing of the inserts.

Fat Lady

The nickname of the GMT-Master II Ref. 16760 refers to its thicker case, larger crown guards and wider lugs. Ref. 16760 GMT-Master II manufactured between 1983 and 1988 with a red and black bezel only, so named because its case is 1mm larger than its counterparts.


Refers to the DateJust II 116333 slate dial. See also Wimbledon.

Feet First

Indication of the possible dive depth in feet and then in metres.

Finition (Finishing)

The watches are finished in three types of finish, a polished surface, a brushed finish and a gold-plated finish.

Flat four (fat four)

Refers to the 4 of some Rolex inserts. It is flat on top. It is sometimes read as Fat Four to mean Flat Four.


Featured on Rolex’s extreme dive watches such as the Sea-Dweller and Deepsea, the Fliplock extension allows the Oyster bracelet to be adjusted by an additional 26mm to accommodate thick wetsuits.


Deployment buckle closure system.


Characterises the first series (R) produced of the Daytona 16520. The “cosmograph” script is detached from the rest of the literature. Also refers to the literature of some 6263s, the Daytona is detached from the 6 o’clock counter.


Refers to the finish of the cases, bezels and straps of certain Day Date and DateJust watches.

Florentine finish (Morellis)

On the president’s bracelets – looks like a hatched pattern – very rare.

Flute / groove

Grooves are small grooves made along a shaft, stem or button so that we can grip it firmly without our fingers slipping. We see these grooves on the crown of the winding mechanism, for example. The term “fluted” refers specifically to the gold bezels on Rolex watches, which are carved with small, elegant bevels.

Fluted bezel

Refers to a type of bezel which is not smooth but whose shape is based on triangles (DateJust, DayDate…). The fluted bezels have originally a very precise function: to screw the bezel on the case to guarantee the waterproofness. Today it is an aesthetic symbol available on the yellow gold, white gold and everose models.


A second hand on a stopwatch that can be used to time laps or to determine the finishing times of several competitors in a race. Start the stopwatch, setting the flyback hand and the normal stopwatch second hand in motion. To record a lap time or finish time, stop the flyback hand. After recording the time, press a button and the hand will move back to catch up with the elapsed time hand in constant motion. Repeat the process to record as many lap times or finish times as required. In chronographs with digital displays, a “function” has the same effect.


The Flyback is a function originally designed for aircraft pilots. This complication allows the chronograph function of the watch to be stopped, reset and restarted at the touch of a button.

Fold-Over Clasp

A three-part closure that secures both ends of the strap and leaves enough room to place the watch on the wrist when fully deployed. When closed, the buckle covers the two-part folding mechanism. The folding clasp is a clasp that folds nicely into the strap for added elegance.

Folded bracelet

Refers to the method of assembling the bracelet. The links of the bracelet are folded on themselves.


Refers to the small GMT hands.


Refers to the reference 1655 (Big Arrow or Steve Mc Queen). The term is inspired by the Italian word for orange arrow (contraction of “freciatta/arancione”) to designate the large second time zone hand.

Full set

A watch including the original packaging, box (over-box), paper (certificate and booklet), COSC tags, calendar, anchor, etc… The set differs from one model to another.


Also known as complications. A term used to describe the different tasks a watch can perform, such as chronograph and countdown.


Gear train

The gear system that transmits power from the mainspring to the exhaust.


Refers to the final stage of the faded insert (see letter F). An insert that has been worn down to such an extent that the graduations can no longer be read.

Ghost hands

Refers to Rolex’s three-pronged hour hand. For some, it refers to the swimmer Mercedes Gleitze who was the first to swim across the English Channel. She wore a Rolex Oyster during her feat. For others, it’s just a technical need to fill the hand with luminescent material.

Ghost watch hands

Refers to the hands of Explorer 2 watches with a black dial, the base of which is the same colour as the dial.


Name of the meteorite in which the “meteorite” dials are made.


Submariner from the late fifties to the nineties with dial printing finished in gold. Refers to the printing on the dial. Made in a gold or very off-white colour.

Gilt dial

Refers to dials with gold writing.


The Glidelock system, patented by Rolex, was originally created to adjust the length of Rolex watches when worn on a diving suit. This very practical innovation can be found on the latest generations of Rolex Submariner watches and allows the watch strap to be extended by up to 20 mm without the use of tools.


Like the Fliplock, the Glidelock clasp also allows the strap to be extended to fit a wetsuit, but this time to a length of 20mm in 2mm increments. In addition to the Sea-Dweller and Deepsea, the Glidelock is also fitted to the Oyster straps of the modern Submariner dive watches.


El revestimiento de la esfera hace que ésta tenga un brillo altamente reflectante.


In watchmaking, GMT (Greenwich Mean Time) is the name of a complication that simultaneously displays the time in two time zones. Originally created for the US Air Force, this function allows the wearer to set the time of the time zone in which he or she is located and that of the time zone of his or her country of origin. This is why timepieces equipped with this complication have always been associated with world travellers, such as pilots.

GMT Time Zone

Greenwich Mean Time (GMT) is also known as Zulu time and UTC (Coordinated Universal Time). The standard by which world time is defined was agreed at the 1884 International Meridian Conference in Washington DC, USA. It placed Greenwich on the prime meridian (zero longitude). Greenwich Mean Time or GMT is the time standard to which all other time zones in the world refer. It is the same throughout the year and is not affected by daylight saving time or summer time. GMT was originally introduced to facilitate naval navigation when the globe began to open up with the discovery of the “New World” (America) in the 15th century. In general, when the term GMT is used with watches, it refers to the ability of the watch to display the local time and the time of at least one other time zone in 24-hour mode. The reason for displaying the additional time zone in the 24-hour mode is to allow the wearer of the watch to know whether the second time zone is in AM or PM.

Gold (White / Yellow / Pink / Red / Grey)

Gold is a noble material that is widely used in jewellery and watchmaking. The most common gold alloy is 18K. With a hardness of 3 on the Mohs scale, compared to 10 for diamond and 6 for steel, gold is a very malleable precious material. Therefore, it requires great care. Yellow gold is an alloy of 75% pure gold, 12.5% silver and 12.5% copper. White gold is an alloy of 75% pure gold, silver and sometimes palladium. Rose gold is an alloy of 75% pure gold, 20% copper and 5% sterling silver.

Gold crystals

Exclusive dials obtained by a gold crystallization process developed by Rolex and produced in its own foundry. The dials can be coloured in yellow, white or pink gold or decorated with galvanic or PVD patterns.

Gold plated

The application of gold to the surface of an article. The thickness of the plating is measured in microns (1000th of a mm).

Goldust Dream

Mother-of-pearl dials with decorative openwork designs in a thin layer of gold or platinum.

Grande Complication

A Grande Complication is a combination of complications but must include a perpetual calendar (with or without moon phase indication), a split-seconds flyback chronograph and a minute repeater. Manufacturers often include many other complications.


Refers to the characteristic shape of some Rolex Precision watches. Their horns give them a grasshopper-like appearance. 4514, 4417, 4332…


Designates, in the same way as Grazieta, the typography of certain Comex logos.

Great White

A ref. 1665 Sea-Dweller, with the characteristic red text replaced by an all white font on all four lines of text.

Green Rolex

This is the colour Rolex uses to ‘celebrate’ an event. Examples include the green bezel on the 50th anniversary Submariner, the green crystal on the Rolex Milgauss and the green dial on their gold GMT-Master II.

Guichet Date

A small opening in the dial through which the date is displayed.


It is an engraving technique in which a very precise and complex repetitive pattern or design is mechanically engraved into an underlying material in very fine detail. More specifically, it is a turning technique, called guilloche in French, after the French engineer “Guillot”, who invented the machine capable of engraving fine patterns and designs on metal surfaces. Guilloché is a decorative engraving technique, used on the watch face and some other components, in which straight lines and curves intersect or intertwine. Guilloché can be done with a chisel or a lathe.



The movement stops completely when the crown is pulled out.


Also known as a balance spring. A very thin spring in a mechanical watch that causes the balance wheel to recoil. Its length and adjustment are used to regulate the timing of the watch.

Hand Ball

Refers to the second hands with the ball at the end.

Hand-wound mechanical movement

A manually wound mechanical watch must be wound by hand. To wind the mainspring of the watch, you turn the crown of the winding mechanism. The movement transmitted by the user’s fingers to the crown is transmitted to the movement by the winding stem to the barrel, through a series of gears to the mainspring.

Hecho in Mexico

For a time, some President’s bracelets were made in Mexico and stamped as such.

Helium valve

The valve on Rolex Sea-Dwellers and DeepSeas that opens automatically when ascending from the depths. Without this valve, the watch glass would explode due to the excessive pressure that can build up during a dive.

Helium valve (or H.E.V.)

Valve that allows helium to escape when diving and depressurises the watch. Used on Sea-Dweller, DeepSea but also 5514 and Comex watches.

Hidden Clasp

A type of clasp on modern jubilee and presidential bracelets which, when closed, gives the impression that the bracelet is continuous, the clasp mechanism being hidden.

High polish

Polishing style for bracelets, cases and bezels, with a mirror finish.

Holes case (Drilled Case)

Like the drilled lugs, these holes make it easy to change the strap or bracelet of your watch.


Three-coloured checkerboard pattern resembling the fabric pattern of the same name.


The nickname of the Submariner ref. 116610LV in reference to the rich green colour of the watch. The Submariner with green dial and green-cerachromic bezel launched in 2010 to replace the Kermit. Ref. 116610LV to its colleagues.



Small sticks, circles, triangles, Arabic or Roman numerals, …. arranged on the dial to identify the 12 different hours.

Index sticks

A type of index which looks like long rectangles without dots and which may or may not be illuminated.

Inverted 6

On some Daytonas the 6 on the hour counter is reversed and reads like a second nine.


James Bond

The nickname of the vintage Submariner ref. 6538, worn by Sean Connery in Dr. No on a NATO-style striped textile strap. Submariner Oyster Perpetual – used as a “brass knuckle” weapon in the original books, also seen in several of the early 007 films – and worn by Bond writer Ian Flemming.

Jubilee bracelet

Created in 1960 for the GMT, later adapted to the rest of the Rolex range. Initially, the crown of the clasp was placed at the edge of the folding clasp to make it easier to open the bracelet. It has the reputation of being very comfortable.

Jumping Hours / Minutes

A jumping hour indicator replaces the hour hand. It indicates the time by means of a digit in a window on the watch face. The word “jump” refers to the fact that the digits jump from 1 to 2 to 3, etc., instead of indicating the intermediate times between the hours as the hour hand does. The minutes and seconds of a jumping hour watch are normally read from the analogue hands and dial.

Jurassic Park

Refers to the Day-Date 18238 dial made from a fossil.



Karat is the unit of measurement for the fineness of gold alloys. We know 9K, 14K, 18K and 22K gold, as well as 24K gold, the purest form of gold, also called “fine gold”. The most common gold used for watch cases is 18K alloy, which contains pure 18/24 or 750/1000 gold. When spelled “carat” and abbreviated “ct”, the carat also refers to the international unit of weight of precious and semi-precious stones.


The nickname of the Submariner 50th Anniversary Ref. 16610LV in reference to its green aluminium bezel. Submariner with black dial and green bezel launched in the year of its 50th anniversary in 2003, often preferred to the Hulk’s greenwash. Also known as reference 16610LV.

Killy (Jean-Claude)

An ultra-rare version of the only combination chronograph and full calendar ever made by Rolex, known (also colloquially) as the Dato-Compax and named after the triple gold medal-winning Olympic skier in 1968 who wore one and became a Rolex ambassador. Produced between 1940 and 1960 in four references, of which the 6236 is the last and, perhaps, most desirable.

King Sub

Designates the Submariner 6200. (dial 3-6-9). There are several types of dials, including a “small size.

Kissing Four

Designates inserts where the 4 touches the 0 of the “40”.


"Long Five" bezel

Designates the MK2 inserts. The inner loop of the 5 is more elongated than on the MK1 (upper part).


Slang term for condition and short for “like new in the box”.

Lap Timer

A stopwatch function that allows the wearer to time segments of a race. At the end of a lap, the wearer stops the stopwatch, which then resets to zero to start timing the next lap.


Metamorphic rock containing silicates of the feldspathoid group. It may have been used to make deep blue dials.


Designates a very rare left-handed Day-Date (crown on the right).

Linen dial

A type of finish on some Rolex dials – looks like linen paper, small fibre-like particles on the dial.


Refers to military-dial Oyster watches made for Canada in the 1930s-40s. The majority have the Rolex 59 calibre (modified FF30), which is fully marked both Oyster Watch Co. and RWC, Ltd. There are also Oyster Edison, Oyster Raleigh, Oyster Centregraph, Oyster Junior Sport, Oyster Commander, Oyster Recorda, Oyster Grenfell, Oyster Shipmate and Oyster Standard.

Liquid Crystal Display (LCD)

The liquid crystal display (LCD) is a digital watch display that shows the time electronically by means of a liquid held in a thin layer between two transparent plates. All LCD watches are equipped with quartz movements.


A slang term for a second hand with a luminous point at the extreme tip. It is commonly found on the Tudor Submariner ref. 6204

Long Drive Chronometer

The “SUPERLATIVE CHRONOMETER” writing is longer (from 7 o’clock to 5 o’clock) than on the so-called normal dials.

Long E

Particularity of the “E” typeface of Rolex on some dials (GMT 1675).


Double extension of the middle by which a bracelet or strap is attached.


A ring on the top of the case surrounding the crystal. It can be decorative or functional. The bezel can be fixed, move in one direction (unidirectional) or in both directions (bidirectional). Many functional bezels allow the time to be calibrated from a given point by rotating the position of the bezel relative to a given starting reference point along the dial.The metal ring on the outside of the glass. Over the years, Rolex has used a variety of materials to make its bezels. The most common materials used for Rolex glasses are steel and their patented Cerachrom material. Other materials commonly used by Rolex for their eyewear include bakelite and aluminium.



The tree from which some Rolex “wood” dials are made.

Main spring

The spiral spring that provides the energy to drive a mechanical watch movement.


Family of mineral carbonates. Used to make certain dials.


French term for a watch factory which itself produces the components needed to make watches.

Marine Chronometer

Arguably the most accurate timepiece in the world, a marine chronometer is a mechanical or electronic timepiece enclosed in a case and used to determine longitude on board a ship. Marine chronometers with a mechanical movement are mounted on gimbals so that they are in the horizontal position required for accuracy.

Mark (MK)

Refers to the differences on a model which has not changed reference (difference of dial, insert, etc…). The different versions are noted MK1, MK2, …

Maxi dial

A modern term for a dial with oversized hour dots, mainly used to describe submariners and GMT models.

Measurement conversion

A function that allows the wearer to convert one type of measurement into another. It usually consists of a graduated scale on the bezel or dial.

Mechanical movement with automatic winding

A mechanical watch that uses the addition of a weighted pendulum called a “Rotor” as a power source. The rotor is attached to the movement, when the watch is in motion and worn continuously, the natural movements of the body cause the rotor inside the watch to turn and “automatically” wind or power the movement. If worn daily, an automatic watch will not need to be wound. An automatic watch can and should be wound manually if the watch has stopped or reached the end of its power reserve due to non-wear. To restore the power reserve of an automatic watch, it is sufficient to wind it 30 to 40 times. You can’t wind an automatic watch too much. Winding an automatic watch by hand after the power reserve has been exhausted or the watch has stopped ensures that the power reserve is complete. The typical power reserve of an automatic watch is 35 to 45 hours. See your manual for more details.


Dial made from a thin slice of a real Namibian meteorite that fell from space.

Meter first

Dials whose water resistance (given in maximum dive depth) is indicated in “metres” first before being converted to feet (=ft). The reverse for feet first.


This is one thousandth of a millimetre and is a measurement used for the thickness of the gilding.


This is the military version of the Submariner (5513/5517). These watches with this specific type of dial were exclusively intended for Royal Navy divers. The T indicates that the “sword” hands and indexes are tritium.

Mineral glass K1

K1 mineral glass is a toughened mineral glass that is much harder than normal mineral glass. The glass is manufactured by grinding and not by heating. The following comparison can be used as a guide: Vickers hardness test: sapphire – approx. 1900, K1 – approx. 700, mineral glass – approx. 380 Mohs hardness scale (from 0 to 10, diamond hardness is 10): sapphire – approx. 9, K1 – approx. 6, mineral glass – approx. 4


Condition Description – refers to a watch that is almost new. Usually, some simple maintenance and light polishing has been done but the watch has retained its original luster.

Minute repeater

A watch complication that allows the time to be struck in hours, quarters or seconds by means of a pusher on the case. One of the most expensive complications of a mechanical timepiece.


Refers to the Rolex Daytona ref. 116598 SACO. The term refers to the Zairean dictator for his leopard hat.

Mono Pusher Chronograph

A stopwatch operated by a single button. While 99% of chronographs are operated by the use of two buttons – one to start and stop the stopwatch, the second to reset it; a Mono Pusher complication allows the use of a single button to start, stop and reset the stopwatch.


Ref 6202 (from 1953). It is sometimes considered as the first Submariner.

Moon phase

The moon phase is a complication that indicates the different phases of the moon. A lunar cycle lasts 29 days, 12 hours, 44 minutes and 28 seconds and consists of 4 phases: new moon, first quarter moon, full moon and last quarter moon.

Mother of Pearl

Iridescence is an optical phenomenon that gives mother-of-pearl its characteristic shine and produces a rainbow of different colours depending on how the light hits it. The inside of some shells is made up of several thin layers of material, which are responsible for this shimmering effect. Pearls are created in a similar process. The thin layers break up and reflect the light differently, resulting in a spectrum of colours that can also be found in a rainbow.


The set of parts that come together to make a watch work. In a mechanical watch, the movement includes the winding and time-setting mechanism, the gear train, the escapement and the balance spring. While the average watch movement has 130 parts, the most complicated movement in the world, designed by Patek Philippe, has 1,728 parts.



Anglo-Saxon abbreviation for parts that have never been sold but are not the most recent model – “new old stock”.


References the military fabric bracelet worn by James Bond in Goldfinger. Alternating black, burgundy and khaki stripes. Be careful to choose it too small. (choose the 18mm instead of the 20mm for a total look). Note 3 variations, the black nato bond / 2 grey stripes, the Regimental Bond, black / 2 grey stripes / 4 red edgings and the Real nato bond, black / 2 olive green stripes / 4 red edgings.


Refers to a specific dial pattern on vintage Rolex GMT-Master and Submariner watches that features faceted gold nipple-like markers. Dial style with raised applied dots at 1, 2, 4, 5, 7, 8, 10 and 11 o’clock.

No Date

Indicates the absence of a date function on some models – this is not an official Rolex term. If a model does not have a date function, Rolex simply refers to it as an Oyster Perpetual, i.e. the Oyster Perpetual Submariner as opposed to the Submariner Date.



Designates watches for the Italian police (with the Octopus).


Refers to olive-shaped push buttons.


Refers to Rolexes with a marking from the Sultan of Oman.


Natural mineral stone dial – solid black.

Onyx dial

Mineral from which some dials are made. Onyx is a variety of chalcedony composed of SiO2 (silicon dioxide).


1 Oscillation = 2 alternations / 4 Oscillations per second = 28’800 alternations per hour.


In Italian, big egg. Big Egg in English. Designs the “big” Bubbleback Ref.6084/6085. Name given because of the curves of these references.


The very first waterproof watch bears this name. Since then, the Oyster “label” certifies that the watch is waterproof. Created and patented by ROLEX in 1926, the watch is called Oyster because it is hermetically sealed like an oyster shell thanks to two technical innovations: a screwed back and a patented winding crown. It is therefore resistant to prolonged immersion in water and, above all, is protected from dust, “the watchmaker’s greatest enemy”.

Oyster bracelet

One of Rolex’s famous bracelets, the Oyster sports bracelet has been around since the 1930s and features a three-part flat link configuration.

Oyster Perpetual

Label given to Rolex watches that include a water-resistant Oyster case and a self-winding “perpetual” movement. All modern Rolex watches (except the Cellini collection) are part of the Oyster Perpetual family. It should not be confused with the Oyster Perpetual model, which is Rolex’s entry-level self-winding watch.


The name given to Rolex’s polymer-based straps, first introduced on the Yacht-Master 40 in 2015 and increasingly available across the Oyster range. At its heart is a thin, flexible metal blade made from a titanium/nickel alloy, encased in a high-density elastomer. But don’t call it a rubber strap.


The name Rolex uses for its stainless steel (as of 2018). This is the same 904L grade steel that Rolex has used since 1985, which is polished to a high standard. Adopting the name Oystersteel does not mean that Rolex’s case finishing has improved; rather, it is a formalisation of existing production processes.


"Pepsi" bezel

This term is commonly used to refer to the blue and red inserts on the bezel of the GMT-Master and GMT-Master II models.


Refers to the 8171 with triple date and moon phase produced in the very late 1940s. Padellone means large stove. Why large pan? Because of its 38 mm diameter which was considered large for the time…

Painted indexes

Refers to indexes that are not circled. They are simply painted on the dial (until 84-85).


A term used by Italian collectors to refer to the painted indexes on the matte dials of vintage Rolexes. By extension, this term is used to distinguish a matt dial with painted indexes from a glossy dial with circled indexes.

Pan Am

Air king special series for the Pan American Petroleum and Transport Company.


Refers to the white dials and black sub-dials found on the Daytona model. Here in Paul Newman version. It exists under different references: 6239, 6240, 6241, etc…


A collector’s term referring to the colour of a dial. Usually reserved for the Rolex Daytona, the majority of the dial is white while the sub-dials are all black.


A Rolex Daytona with very shiny sub-dials. They can also be called “mirror balls”. The official term is “azure”.


Another Italian word to say that a dial has a patina. Example with the 116520 from 2003 to 2006. Comparison with a Regular Dial.

Panna (or cream) dial

This refers to certain white dials that have developed a patina, notably the Explorer 2 and Daytona.


Thanks to the Spiral Parachrom, our watches are insensitive to magnetic fields and are more resistant to shocks (Tennis, Golf).


Anti-shock system mounted on some Rolex watches like the Deepsea and the DayDate-II for example.

Patent Pending

Designates the MK1 dials of the 1665. Rolex provided some examples to test the helium valve in 1967 (developed with Doxa). The case back is engraved “Patent Pending”. The SUBMARINER 2000 line is much more SEA-DWELLER than the other MK. The red markings can be faded to pink as they were painted on a white writing base. A very rare example.


A term often used in vintage Rolex collecting circles to describe the change in colour of parts of the watch – hands, indexes, dials, bezel markings – over time. This can range from off-white to a rich brown hue.


A type of Daytona 16520 with brown and faded chapter rings, named after a piece from auctioneer Osvaldo Patrizzi’s personal sale in 2006. Collector Osvaldo Patrizzi was the first to notice that the W and S (sometimes T) series sub-counters took on a brown patina over time.

Paul Newman

The label given to particular vintage Daytona models (ref. 6239, ref. 6241, ref. 6262, ref. 6263, ref. 6264 and ref. 6265) that are fitted with “exotic” Art-Deco style Rolex dials after the famous actor wore one himself. The Paul Newman Daytona he wore himself recently became the most expensive wristwatch ever sold at auction when it sold for $17.8 million in October 2017.


Pronounced “pah-vay” – a jewellery term for the setting of diamonds that completely cover an entire surface. In Rolex parlance, it usually refers to an entire dial, but can also describe an entire watch, for example the GMT glass.


Pointed crown guards – on some vintage sports models. The crown guards stand up in a pointed fashion, in contrast to the rounded style of modern cases.


High-end Rolex model for women available in solid gold only.

Pearlmaster bracelet

In 1992, Rolex launched a more precious version of the ladies’ Datejust with the Pearlmaster jewellery watch. In addition to its gold construction and gemstones, the watch features a Pearlmaster bracelet with five-part rounded links and a crown clasp.


The nickname of the GMT-Master II ref. 16710 and 126710BLRO refers to the black and blue Cerachrom ceramic bezel of the watch.


An old term for a self-winding watch.

Perpetual Calendar

The perpetual calendar is a complication that indicates the date, day and month and automatically takes into account whether a month has 28, 29, 30 or 31 days, whether it is a leap year or not. With this complication, the change from the end of the month to the first of the month requires no adjustment.

Perpetual motion

In 1931, Rolex invented the world’s first automatic movement driven by a Perpetual rotor, called the Perpetual Movement. This ingenious mechanism is not only at the heart of every Rolex automatic movement, but it has also provided the basic structure for almost every modern automatic watch thereafter.

Pie Pan

Refers to DateJust dials that are not flat, they form an angle at the edge.


Named after the famous Italian collector Marcello Pisani. Designates the MK1 dials of the 1665 COMEX. The depth is 600m instead of 610 and the crown is also specific.

Platinum (material)

A rare precious metal, platinum is also one of the strongest and heaviest, making it a popular choice for setting gemstones, jewellery and watches. It has a rich, white lustre and an understated appearance. Platinum is hypoallergenic and resistant to tarnish. Platinum used in jewellery and watches is at least 85-95% pure. Many platinum watches are produced in limited editions due to the cost and rarity of the metal.


Plexiglas crystals, a type of plastic, were used in the 1970s and 1980s. Today, they have been replaced by sapphire crystal. Today, Plexiglas is only found on vintage watches or on re-editions of these watches, which retain the aesthetics of their predecessors.

Pointed Guard (ou Pointed Guard ou Cornino)

Thinner, pointed shoulder to protect the crown.


Refers to the white dial versions of the Rolex Explorer II watches.


An operation performed by a watch specialist to restore a stainless steel watch case or bracelet to its original appearance by removing all micro-scratches, with a flat or shiny finish. Gold watches are also polished.


Refers to certain dials of 16520 series R (up to L for gold: 16528). The colour of the dial is brighter than on the classic versions.

Power reserve

Also known as the power reserve indicator. A function that indicates when the mainspring of the watch will need to be wound. This is a very useful complication for mechanical watches and is usually indicated in hours, except in the case of watches with a very high power reserve that count days.

Power reserve indicator

Also known as the Power Reserve, this feature indicates when the mainspring of the watch should be wound. This is a very useful complication for mechanical watches and is usually indicated in hours, except in the case of watches with a very high power reserve that count days.


Reference 6238. Produced between 1962-1967. Smooth bezel without tachymeter indication (the scale is on the dial). Uniform counter and dial.


The nickname given to Rolex Day-Date watches in reference to both its President’s bracelet and its status as the watch of choice for world leaders, captains of industry and celebrities.

Président bracelet

Exclusively for the DayDate, made of gold or platinum, this bracelet represents excellence and prestige while combining a unique wearing comfort. President can also refer to the Day-Date equipped with this bracelet. This name refers to Eisenhower. He was given this model for his re-election in 1956.

Pulse meter

A scale on a stopwatch that is used to measure pulse rate.


Refers to the 6239 which has a pulsometric scale on its dial.

Punched papers

Refers to papers (certificates) where the numbers have been written by perforating the sheet.

Push button (Pusher)

A button that is pressed to operate a mechanism. Push buttons are usually found on chronographs, striking watches and alarms.

Pussy Galore

Small name of the GMT Master 6542 (produced between 1954 and 1959). The name refers to the character Pussy Galore in the James Bond film Goldfinger. She wears a beautiful 6542.


Physical Vapour Deposition, or PVD, is a metal coating process. This surface treatment is applied to the case and bracelet of a stainless steel watch, resulting in a unique black finish.


The dial is segmented into a grid with each square containing three-dimensional pyramids oriented towards the crystal.



A style of dial in which the dial is divided into 4 quarters. Sometimes the quarters were painted in different colours or only two were painted.

Quartz Crystal

Quartz is a piezoelectric material, which means that it generates an electrical charge when mechanical pressure is applied. These crystals also vibrate when a voltage from an external source, such as a battery, is applied. Piezoelectricity was discovered by Pierre Curie and his brother Jacques in 1880. In the early 1920s, W.G. Cady recognised that because of their elastic qualities, mechanical strength and durability, quartz crystals could be used to make very stable resonators. Cady also concluded that the crystal could be specifically cut to create resonators of almost any frequency, virtually independent of temperature variations. Quartz crystals were first used as a time standard by Warren Marrison, who invented the first quartz clock in 1927. In the early 1970s, Juergen Staudte invented a method of mass producing quartz crystals for watches.

Quartz movement

A calibre that uses the vibrations of a tiny crystal to maintain timekeeping accuracy. Power comes from a battery that needs to be replaced every 2-3 years or so. In recent years, new quartz technology has enabled the watch to recharge without having to replace the battery. This energy is generated by the movements of the body, as in an automatic mechanical watch, or powered by light through a solar cell (Kinetic & solar-tech). A quartz movement works thanks to a quartz band (a mineral) which transmits its vibration frequency to the watch circuit. This vibration is possible thanks to the energy provided by a battery and not by manual or automatic winding, as is the case for a mechanical watch.


"Ring Command" bezel

Featured on the Yacht-Master II and Sky-Dweller models, the Ring Command bezel controls parts of the mechanical movement and works in conjunction with the winding crown to set and adjust various watch functions.


Radioactive luminous material for hands and hour markers – used in antique watches before the 1950s.

Rail Dial

Dials where the two lines of literature (superlative chronometer officially certified) mark their space in the same place. i.e. the “e” in SUPERLATIVE ends above the “y” in OFFICIALLY and the C in CHRONOMETER is just above the C in CERTIFIED. Signature of one of the Rolex dial makers (STERN).


Designates the “art deco” railroad case of certain “Prince” models.

Rainbow (Daytona)

Designates the Daytona whose bezel is set with a sapphire gradient reproducing the shades of the rainbow. Red, orange, yellow, green, blue, mauve and pink.

Random (serial number)

These are the new (random) Rolex serial numbers. They are composed of letters and numbers with no known logic.


A rangefinder scale can be used to calculate the distance between an acoustic signal and one’s own position. Or, more simply, it can be used to determine the proximity of a thunderstorm. To do this, the chronograph is started when the lightning strikes and stopped at the first thunderclap. It is then possible to estimate the distance of the storm by reading the telemetric scale and using the second hand as a counter. The scale is based on the well-known value of sonic velocity (343 m/s or 1235 km/h), and was originally used in a military context. It was used to determine the position of the enemy through muzzle flashes and cannon fire.

Rattrapante (double chronograph)

A watch with a double chronograph has two second hands. One hand is superimposed on the other. While one hand is moving continuously, the other can be stopped, started or reset in order to estimate two separate events of different durations.

Rayon flammé de la gloire

Refers to the guilloche pattern on the dial of the Cellini Dual Time.

Rectangular Dial

Refers to dials where the 2 in GMT Master 2 forms a rectangle. Above for comparison a Stick Dial.

Red Quarter

Designates the red marking of the quarter indicators.


A Regulator display separates the minute and hour hands on a separate axial and sub-dial. This allows the time to be read accurately at a glance, without the watch hands covering each other.


Another term for the inner reflective ring located just above the dial. On all modern models, this area is now engraved with the watch’s serial number and the word Rolex repeated around the ring.


A repeater is a complication that indicates the time by sounding a bell on demand. There are several types of repeater: quarter-hour repeater, five-minute repeater and minute repeater. When you push the pusher, small hammers strike a gong, producing a very delicate sound. For example, with a minute repeater, hours are indicated by a low note, quarter hours by a low note followed by a high note and minutes by a high note.


This is a hand on the dial of a watch that returns to zero at the end of a given period, i.e. days/months. For example, a watch may have a retrograde date, which means that the hand moves up the scale one day at a time, pointing to the current date, and when it reaches 31, it returns to 1.


For complete movement maintenance, disassembly, ultrasonic cleaning, reassembly, oiling, synchronisation and regulation.

Ringlock System

Featured on the Deepsea dive watch, the Ringlock system consists of a central ring of nitrogen-alloyed steel, a 5.5mm thick domed sapphire crystal and a titanium caseback. This system allows the Deepsea to dive safely to 3,900 metres (12,800 feet) – well beyond the depth at which a person can survive.

Riveted bracelet

Refers to the method of assembling the bracelet. The links are riveted.


A Rolex patented term meaning stainless steel and platinum on the same watch – commonly found on the Yachtmaster model.


Part of the Rolex lexicon since 1933, Rolesor refers to the use of gold and steel on a Rolex watch. Often referred to as two-tone, Rolesor can mean a combination of yellow gold and steel, rose gold and steel, or white gold and steel. Term patented by Rolex.

Rolex engraved crown (on the sapphire)

Micro engraving on the sapphire at 6 o’clock (appearance 2003). The ideal way to see it is to shine a low light on it.

Rolex Vintage

Generic term for any Rolex over 30 years old.

Root Beer

Refers to the brown and bronze bezel found on some GMT-Master and GMT-Master II models.

Rotating bezel

A bezel (the ring surrounding the watch face) that can be turned. The different types of rotating bezels perform different timekeeping and calculation functions.


The part of an automatic (or self-winding) mechanical watch that winds the mainspring of the movement. It is a flat piece of metal, usually in the shape of a semi-circle, which pivots on a pivot according to the movement of the wearer’s arm.

Roulette wheel

Designates the date stamp of some DateJusts that displays odd days in red and even days in black.


In watchmaking, a synthetic ruby is used to make low-friction bearings in which the delicate pivots of the movement wheels move. In some luxury watches, sapphires or garnets are sometimes used. Luxury watch movements are adorned with rubies, from the barrel to the balance wheel, and all automatic, date and complication movements are supposed to be adorned with rubies.


Sapphire glass

Sapphire crystal is a very hard transparent material commonly used for “scratch-resistant” watch glasses. Made by crystallising aluminium oxide at very high temperatures, it is chemically identical to natural sapphire and ruby, but without the small amounts of other elements such as iron, titanium or chromium that give gemstones their colours. Sapphire (whether natural or synthetic) is one of the hardest substances, measuring 9 on the Mohs scale, a system for assessing the relative hardness of materials to scratches. (Diamond measures 10, the highest rating, and the hardest steels are at 8).


Annual calendar mechanism developed by Rolex, whose design is directly inspired by the astronomical phenomenon of the same name. It allows the Sky-Dweller calendar to automatically distinguish between 30-day and 31-day months. The calendar only needs to be adjusted once a year, on March 1st, as February has only 28 or 29 days.


Polish style for bracelets and cases.

Seal of Geneva

The Geneva Seal is a standard of excellence created in 1886 to promote and guarantee the quality of Geneva watchmaking. Today, it remains a benchmark of quality and a guarantee of expertise. To receive the famous stamp, a movement must meet several criteria concerning its place of manufacture, its craftsmanship and its reliability. Thus, the Geneva Seal is often awarded to exceptional models of major watch brands whose movements have been assembled, adjusted and cased in the canton of Geneva.

Second Time Zone Indicator

An additional dial that can be set to the time of another time zone. It allows the wearer to follow the local time and the time of another country simultaneously.

Sector Dial

The dial is divided into several sectors. When it forms a cross -as here- it is also called Crosshair.

SEL (Solid End Links)

Rolex bracelet with the end link directly integrated into the bracelet and not an independent end piece. It makes the junction between the case and the bracelet.

Serif (Graziata)

The typography of certain inserts or dials. The numbers or indexes have a serif typeface.

Serif (or Graziata)

The typography of certain inserts or dials. The numbers or indexes have a serif typeface.

Sharks Teeth

Refers to dials with indexes in the shape of sharks’ teeth (6530 from the 1950s).

Shock absorber

A resilient bearing that absorbs shocks to the watch’s balance and protects its pivots from damage. As defined by U.S. government regulations, the ability of a watch to withstand an impact equal to that of a fall to a wooden floor from a height of one metre.


Refers to dials marked “o T Swiss T o”. In other words, a gold set (index and hands).


Refers to the numbers outside the words SWISS or TSWISST. If present, it indicates that the hour markers are white gold. Only used for a short time and not very common.

Single Red

The Submariner 1680 (the first one with date) with “Submariner” in red writing, produced from 1966 to 1973.


A watch whose case and various parts of the movement are made of transparent material, allowing the main parts of the movement to be seen.

Skeleton watch

The watch has a sapphire crystal on the front and back allowing a detailed view of the movement without opening the watch.

Small second

In contrast to the central seconds hand (the seconds hand then shares the axis of the dial with the hour and minute hands), the small seconds hand is positioned in a separate dial of reduced diameter, generally placed at 6 or 9 o’clock.


The nickname of the Submariner in white gold ref. 116619LB refers to the vibrant blue colour of the watch.

Solar battery

Batteries in a quartz watch that are charged by solar panels on the watch face.

Solid lugs

Refers to the fact that the lugs are not pierced on the outside to access the bracelet pumps. Appearance of full horns around 2003 / end of Y series.


Dial that highlights small dots of different colours in the sun.


A collector’s term specifically for glossy black dials, usually Sumbariner, where the dial cracks and splits leaving a spider web pattern in the lacquer.


Very thin spring. The heart of the watch. It is attached to the balance wheel and swings back and forth regularly.

Spiral "Parachrom"

The oscillator, which regulates the precision of a mechanical movement, consists of a balance spring and a balance wheel. The blue Parachrom balance spring patented by Rolex is resistant to magnetic fields and up to ten times more resistant to daily shocks than standard spirals.

Stainless steel

Stainless steel, an alloy of iron and carbon, is a common material used in watchmaking. There are many types of stainless steel, but the most common variety used in watch cases is 316L stainless steel. Some brands, such as Rolex, use a particular stainless steel, 904L, which is known for its corrosion resistance.


The nickname of the Submariner ref. 126610LV refers to the green bezel and the black dial recalling the colours of the brand’s logo.


This is also wear on the dial. Small dots appear like dust.


Refers to the enamelled (very colourful) Day-Date dials.


Refers to the “step” between the main dial and the sub-dials of the first Paul Newman dials. They are not on the same plane.

Stepping Motor

The part of a quartz movement that moves the gear train, which in turn moves the watch hands.

Sterling Silver

A precious metal. Sterling silver is 92.5% pure silver. The fineness of the silver must be stamped on the metal, sometimes with the initials of a designer or the country of origin as a hallmark. A protective coating may be added to prevent tarnishing.

Steve McQueen/Freccione

The vintage Rolex Explorer II ref. 1655 earned the nickname “Steve McQueen” when it was wrongly published that the legendary actor wore one. He never did – his Rolex of choice was a Submariner – but the nickname stuck. The Explorer II ref. 1655 is also called “Freccione”, derived from the Italian word for “arrow” in reference to the arrow-shaped 24-hour hand. As noted in the “Freccione” section, McQueen did not actually wear an Explorer II with orange hands. What he did wear were Submariners, mainly this reference 5512, a rarer chronometer-certified version of the 5513. His real watch – pictured – was sold in 2009 by Antiquorum for $234,000. Since then, however, the “Steve McQueen Submariner” has been associated with another watch he may or may not have worn, reference 5513 sold in 2018 after being fire-damaged, restored and controversial as to its provenance.

Stick Dial

Refers to dials whose 2 in GMT Master 2 is formed of two sticks. Below for comparison a Rectangular Dial.


Collection of Rolex dials using natural materials. For example: lapis lazuli, meteorite, jadeite, gossularite, onyx, etc.


A watch with a second hand that measures time intervals. When a stopwatch is incorporated into a standard watch, the stopwatch function and the timepiece are referred to as a “chronograph”.


Refers to the wear and tear of a bracelet. The links of the Oyster, Jubilé or Président have become loose over time. A restoration is possible.

Sub-dial or subsidiary dial

A small dial used for various purposes, such as keeping track of the minutes or hours on a chronograph or indicating the date.


Smaller, usually recessed, dial area(s) on a dial that indicate additional information. This is mostly seen on the Daytona, but some Cellinis have sub-dials for their second hand.

Submariner ou SUB

The Submariner is one of the most popular watch models manufactured by Rolex. It was launched in 1954 as a diver’s watch for its ability to withstand moisture and water. It is part of the professional range and is the “iconic” Rolex sports watch.


Non-radioactive luminous material for hands and indexes – on all dials after 1998 – technically identical to Luminova.

Superlative Chronometer Officially Certified

Featured on the majority of modern Rolex watch dials, the “Superlative Chronometer Officially Certified” label indicates that the watch is both COSC-certified as a chronometer and has passed a battery of rigorous in-house tests to deliver the reliability, accuracy and durability we have come to expect from a Rolex watch. In 2015, Rolex redefined the COSC designation to guarantee an accuracy index of -2/+2 seconds per day.

Swiss (Swiss Only)

Transition dial model (luminova / tritium).

Swiss A.O.S.C.

A certificate of origin – A mark identifying a watch that is assembled in Switzerland with components of Swiss origin.


As part of a move towards greater consumer protection and in order to combat Far Eastern counterfeiters who claim to be Swiss made, the Swiss Federal Council laid down in 1993 the rule that a watch must meet in order to qualify as Swiss made. The movement must be of Swiss origin and contain at least 50% Swiss parts. The watch must be cased in Switzerland and pass its final inspection in this country.


Name given to the silicon balance spring. Introduced on the calibre 2236.


T Swiss T

Tritium index.


A common feature of chronograph watches. Measures speed over a predefined distance. The wearer starts the chronograph when passing the start point and stops it when passing the finish. The wearer can read the speed in units per hour on the tachymeter scale. The scale is usually engraved on the bezel or printed on the outer diameter of the dial.

Tachymeter scale

The tachymeter scale is located on the rim of the dial or on the bevel of a watch. It is most commonly found on car-inspired watches. It is used to help calculate the speed of a moving object over a given distance. In effect, the information indicated by the chronograph hand can be read off the tachymeter scale to determine its average speed.


Refers to the patina of the tritium indexes of the Explorer 1655: orange like the hand. Extends more generally to the entire Pro range.

Tapestry dial

Dial with a vertical line design covering the whole dial (a bit like wallpaper).

Taxi Driver

Designates “stella” yellow “taxi” dials.


The little name sometimes given to the 5100 Beta 21 (1970). First Rolex with a sapphire crystal and a Quartz movement.


Paul Newman” non-step dial. They are often identified by specialists as fake dials that appeared in the 90s.

The Real Mc Coy's

Designates a limited edition GMT Master paying tribute to Chuck Yeager’s achievement. He broke the sound barrier in 1947 in his Bell X-1.


The Turn-O-Graph rotating bezel version of the 1950s Datejust, of which Rolex produced special marked dial versions for the USAF Thunderbirds demonstration team pilots.

Thunderbolt hands


An instrument for recording intervals of time (duration, short times), without indicating the time.


A “space age” metal, often with a silver-grey appearance. As it is 30% stronger and almost 50% lighter than steel, it is increasingly used in watchmaking, especially in sports watches. Its resistance to salt water corrosion makes it particularly useful in diving watches. As it can be easily scratched, some manufacturers use a patented coating to resist scratching. Titanium is also hypoallergenic. Titanium is a material frequently used in watchmaking, particularly in the manufacture of cases. It is valued for its corrosion resistance and lightness.


A mechanism that keeps track of the elapsed time and displays it, usually on a sub-dial of the watch face. Similar to a “recorder” or “register”. The term “totalizer” can be used more generally to refer to any counter on a watch.


A device, invented by Breguet in 1801, in which the escapement is mounted in a small rotating cage to overcome the effects of gravity on the precision of a mechanical timepiece. This mechanism, even in its most conventional version, is extremely difficult to manufacture and usually requires a high premium. By mounting the balance, escapement and pallet in a rotating cage, the effects of gravity are compensated for by eliminating the deviations that occur when the watch is in an upright position.


Rolex model which includes some parts of the old reference but also improvements of the following model (calibers and dials for example).


Designates models that are composed of yellow/grey/pink gold. Between the 1980s and 2000, the Tridor is a fusion of the 3 golds with a process that allows no mixing between the materials (costly in production). In the current catalogue, the Tridor is not a fusion on a single piece but an assembly of pieces of the 3 golds.

Triple Six

Refers to the Rolex Sea-Dweller 16660.


This refers to winding crowns with three joints. To recognise them, in steel it has three identical dots under the crown, in gold it still has three dots but the middle one is bigger and in platinum it is the two dots at the ends that are bigger than the middle one.

Triplock / Twinlock crown

The construction of the winding crown, which is screwed to the case to prevent water from entering, is integral to the water resistance of the Oyster case. Twinlock winding crowns have two sealed areas while Triplock winding crowns have three sealed areas to ensure the water resistance of the watch.


Tritium is a colourless gas also known as extra-heavy hydrogen. Its name comes from the Greek word “tritos”, which means “third”, and refers to the three components of the atom (3H). Tritium has been used for decades in all kinds of applications where constant, independent and durable light sources are essential. On military watch dials, you will often find a red circular symbol with the notation “3H” which refers to the use of tritium. In “civilian” watches, the abbreviation “T25” indicates the same thing. In the past, luminous tritium was applied directly to the dial. Today’s watchmakers are more careful and fill the gas into thin tubes of borosilicate glass, a highly resistant, ISO-certified glass used in chemical engineering. These tritium gas light sources (or GTLS) are not only exceptionally safe, but they also guarantee the wearer constant luminance for at least ten years – without any external power source.


Dial has turned brown over time.


Rotating and timed bezel on the DateJust “thunderbird” model.

Turntable (watchmaker's tool)

The base plate on which all other parts of a watch movement are mounted.


A style of dial using 2 colours, usually black and white or silver and steel. Most of the dial is one colour (usually the darkest) and in an outer ring, the other colour.


Designates winding crowns with two seals. To identify them: in steel and gold steel, there is a line under the crown, in gold it is two dots and in platinum a single dot under the crown.


Also called steel and gold, 2 tone and Tu Tone, this term is used to describe a watch made from two different metals – most often stainless steel and yellow gold.



Refers to certain dials which have an underlined statement. When placed under the OYSTER PERPETUAL, it may be referred to as “Upper Underline”.


These are sports models from the early 1950s to the early 1960s, with an underline at 12 o’clock, indicating the use of tritium for the luminous material, when Rolex was in the process of abandoning the use of radium.

Unidirectional rotating bezel

A rotating elapsed time bezel (see “rotating elapsed time bezel”), often found on dive watches, which moves only counter-clockwise. It is designed to prevent a diver who has inadvertently dropped the bezel from its initial position from overestimating his or her remaining air reserve. Since the bezel only moves in one direction, the diver can only make a safety mistake when timing the dive. Many dive watches are equipped with a ratchet that locks them for added safety.

Unpierced case

A case that does not have pierced horns.


A collector’s term for a watch that has never been polished in its life, very desirable to preserve the bevel on sports models.

Unpolished / Never Polished

A collector’s term for a watch that has never been polished in its life, very desirable to preserve the bevel on sports models.

Upside Down

Obviously indicates a Rolex production error on 5512s. Instead of having the serial number at 6 o’clock and the watch reference at 12 o’clock, the opposite was struck. The serial number at noon and the reference at 6 o’clock.



Designates the Rolex reference 6512. It takes its name from the thinnest Oyster case ever produced. This watch embeds a calibre 1000, derived from the 1030, with mechanical winding.

Vibration Per Hour or VPH

The movement of a pendulum or other oscillating element, limited by two consecutive extreme positions. The pendulum of a mechanical watch usually makes five or six vibrations per second (i.e. 18,000 or 21,600 per hour), but the pendulum of a high-frequency watch may make seven, eight or even ten vibrations per second (i.e. 25,200, 28,800 or 36,000 per hour).


Designates the radial gradation of the dials on DateJust and Day-Date.


Watch "Tank"

A rectangular watch with bars on the sides of its face. It was inspired by the tracks of the tanks used during the Second World War and designed by Louis Cartier.


The science of measuring time and the technology of constructing instruments for its measurement or recording. The art of designing and building watches.

Water Resistance

Describes the level of protection of a watch against water damage. A water resistant watch can resist water to a certain extent. Consult the watch manual to find out the exact level of water resistance of your watch. Waterproof watches have specific gaskets and a screw-down crown and caseback for winding. Manufacturers provide water-resistance recommendations for each watch model, with water-resistance levels indicated in metres, ATM or bars. Some watches do not tolerate any contact with water, while others are water resistant to a depth of 300 metres. There are many variations between these two extremes. To find out more about the water resistance of your watch, we recommend that you consult our water resistance guide.


Wide Boy hands

Refers to the large, flat hands and indexes.


Designates the DateJust II 116333 slate dial. It can also be nicknamed the “Federer” because it is closely linked to the Swiss tennis player.


A style of abandoned dial with a piece of wood on the surface. Types of wood used: birch, burl wood, walnut, African mahogany.


A dial, usually located on the outer edge of the watch face, which shows the time in up to 24 time zones around the world. The time zones are represented by the names of the cities printed on the bezel or dial. The wearer reads the time in a particular time zone by looking at the scale next to the city to which the hour hand points. The minutes are read as normal. Watches with this function are called “world clocks”.


Z Blue

Dial reference of the Milgauss blue dial presented in Basel in 2014.


Swiss luxury watch brand. The Rolex Daytona (reference 16520) carried Zenith’s El Primero 400 movement from 1988 to 2000 before Rolex produced its own chronograph movement.

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