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Watch Terminology Watch Terminology


Analogue watches use hands to show the time, not an LCD display.

A watch feature that sounds an alarm at an user-set time or at regular intervals.

A watch function that uses changes in barometric pressure to provides altitude readings.

Analogue Digital
A watch that uses both digital display and hands to display the time. Usually featured on sport watch styles.

Analogue quartz
The most commonly-used term in referring to any analogue watch that is powered by a battery or solar power and is regulated by a quartz crystal.

Ana log Watch
A watch with a dial, hands, and numbers or markers to display the time.

Where the date is displayed within the dial of the watch.

Atmosphere (Atm)
Unit of pressure used in watch making to indicate water-resistance.

Atomic time standard
These watches set their time by receiving radio signals from extremely accurate Atomic clocks.

Auto repeat timer
If the watch timer function is set and started, it will countdown to zero, beep with a warning signal and immediately return to the preset time and start the countdown again. This continues until stop button is pushed.

Automatic watches negate the need for manual winding by using the movements of the wearers arm to move an oscillating weight which keeps the mainspring wound up. When fully wound and left to sit, most automatics will have up to 36 hours of reserve power. Mechanical movements are accurate within one minute each day.

Automatic movement
See 'Automatic' above


Ladies style watch with a thin, elongated rectangular or oval face.

The regulating organ of the watch, vibrating on a spiral hairspring. Lengthening or shortening the balance-spring makes the balance-wheel go faster or slower to advance or retard the watch.

A small rod with a sprung pivot at either end which fixes the strap to the watch.

Base metal
Any non-precious metal such as steel.

Also known as a cell. For replacement purposes, the battery number is found on the case back. The volt in a quartz analogue watch is 1.5V. The volt in a digital watch is 3.0V.

Battery Life
This is the minimum period of time that a battery will continue to power the watch. Life begins at the point of manufacture when the factory initially installs the battery.

Battery Reserve Indicator
The watch will indicate when the battery is nearing it's end by causing the movement of the hands to jump 2-4 seconds depending upon the make and model. This function is only available on some Quartz watches.

The ring on the outside of a watch that surrounds and holds the crystal in place. A rotating ratchet bezel moves in some sport watches as part of the timing device. Some rotating bezels are bi-directional, and can assist in calculations for elapsed times.

A flexible metal band consisting of assembled links which allow the bracelet to articulate to mould itself comfortably to any wrist.

Brushed Steel
Stainless Steel with a Matt 'brushed' effect finish.

The fastening for a strap, consisting of a rim and tongue. It attaches the two parts of the leather strap around the wrist.

Push piece controls to control special functions such as the chronograph or the alarm.


Cabochon crown
A rounded semi-precious stone or synthetic material usually black, fitted into the watch crown as an ornament.

A watch feature that shows the date and sometimes the day of the week and the month, usually displayed through a cut-out window in the dial, or as a small sud-dial with small hands indicating the day/date feature or by digital readout.

The dimensions of the watch. Calibre describes the size and configuration of the movement and can now indicate the shape, origin and constructor as well.

Refers to a curved or arched dial or bezel.

Carat (Karat)
Degree of purity of gold: Pure gold is 24 carat, 18 carat is an alloy of which 75% is gold, 14 carat is 58% gold and 9 carat is 37.5% gold.

Essentially the chassis of any watch, housing of a watch's parts, and to which the strap is fixed.

Case back
The cover on the back of a watch which protects the movement. A case back normally snaps back into place or in the case of a waterproof model will be of the screw down variety to ensure water cannot permeate the seal. Information regarding each watch can usually be found on the outside of the case back.

A multifunction sport watch with stopwatch functions. Most have two or three small dials on the face, for measuring seconds, minutes and hours.

A precision watch that is set in various temperatures and positions, thus meeting the accuracy standards set by an official watch institute in Switzerland. Most watch companies either provide this certificate with a purchase or it can be mailed to you.

The fastening mechanism for bracelet watches. There are many types of clasps

  • Deployment Buckle—A three-folding enclosure, which secures the two ends of the bracelet and allows enough room for placing the watch on the wrist when fully deployed. When closed, the buckle covers the two-piece folding mechanism
  • Fold-Over Buckle—See Deployment buckle
  • Hook Lock—Two separate units each fitting on either end of the bracelet which allows the watch to be laid out. One end of the closure hooks onto the other to secure the two ends of the bracelet.
  • Jeweler's Clasp—A closure that is generally used on better bracelets. Also allows it to lie flat.
  • Sliding Clasp—Also a hook type method but allows for easy sizing of the bracelet by sliding up.
  • Twist Lock—A closure similar to Jeweler's Clasp used on ladies jewelry bracelets.

A watch with other functions besides time keeping. For example, a chronograph is a watch complication. other complications coveted by watch collectors include: minute repeater, tourbillion, perpetual calendar, or split second chronograph.

System to set the watches time by means of the crown.

As with a Chronograph, except that the Tachymeter function is found on the watshes bezel.

Countdown timer
Measures remaining time from preset period of time.

The button that extends from the case that is used to set the time, date, etc. Most pull out to set the time. In water resistant styles, the crowns should screw down.
Used for setting the watch hands (often called the button).

The clean cover over the watch face, commonly known as the glass. Three types of crystals are commonly found in watches.

  • Acrylic crystal, a plastic, is inexpensive and shallow scratches can be buffed out.
  • Mineral crystal is comprised of several elements that are heat treated to create unusual hardness that aids in resisting scratches.
  • Sapphire crystal is the most expensive and durable, approximately three times harder than mineral crystals and 20 time harder than acrylic crystals. A non reflective coating on some sport styles prevents glare.

Dial or Face
The dial sits on top of the movement and is one of the most important ways of giving a watch its own distinctive looks.

Day/date watch
A watch that can indicate the day of the week as well as the date.

Deployment Buckle
A clasp that folds under the strap of the watch.

The watch face that the numerals, indices, or surface design are applied upon.

Any watch that shows the time in numbers instead of hands on a dial.

Directional compass
The geographical direction can be displayed by rotating a bezel or digital readout on the face of the watch using the location of the sun.

Diver's Clasp
A clasp that is suitable to wear over a diving suit

Divers Watches
Diver's watches are designed and manufactured especially for divers whose lives depend on the reliability of their watch in the water. Seiko and Pulsar diver's watches meet ISO (International Standardization Organization) regulations and must meet various standards regarding water resistancy, pressure resistancy, readability in the water, time presetting function (rotating elapsed time bezel), anti-magnetic ability, anti-shock, rust resistancy in salt water, manageability in water, ability to withstand sudden temperature changes, etc.

Dual timer, Duo Time or Travelcentric
A watch that measures current local time as well as at least one other time zone.

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A watch that never needs a battery. Citizen Eco-Drive technology harnesses the power of light - from any natural or artificial light source - and converts it into energy which is stored in a permanently rechargeable lithium-ion battery. It recharges continuously in any kind of light to run forever.

Eco-Drive Vitro
The glass acts as the light energy cell. Located on the top of the glass are very fine strips of amorphous silicon virtually invisible to the naked eye. Electricity is generated as soon as light strikes the glass from the outside and again as it reflects back off the dial. Vitro' runs for approximately six months once fully charged.

Eco-Drive Infinitum
These watches run for approximately 5 years once fully charged (Ladies model 2 years), and feature a perpetual calendar accurate to February 2100. When this watch has not been exposed to light for a certain length of time, the functions begin to shut down. This saves power and extends operating time. In the mean time, the movement's integrated circuit keeps track of the current time and date. When the watch is once more exposed to light, the hands and date immediately resume their correct positions.

End of Life. In quartz movement watches, the battery should be changed when the seconds hand which starts to jump every four seconds.

End of Energy. System used with the AHP alerts the wearer of accumulator discharge by causing the seconds hand to jump every four seconds instead of every second. The accumulator can the be recharged by turning the crown.

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The visible side of the watch where the dial is contained, most are printed with Arabic or Roman numerals. Note: traditionally IIII, rather than IV, is used to indicate the 4 o'clock position.

Flyback hand
A seconds hand on a chronograph that is used to determine lap or finishing times for several competitors. Both the flyback and the regular second hand are set in motion, then to record a lap or finishing time, the flyback hand can be stopped. After taking the results, push a button and the flyback hand will catch up to the constantly moving second hand.


Greenwich Mean Time, used as universal standard time.

A style of intricate engraving that is popular on watch dials, usually very thin lines interwoven to create a surface texture.


The authorised stamp impressed on gold or silver watches that indicate the authentcity of the precoius metals used in the watches construction.

The pointing devices that circle around the dial indicating hours, minutes, seconds and any other special features of the watch.

  • Alpha Hands: A slightly tapered hand.
  • Baton Hands: A narrow hand sometimes referred to as a stick hand.
  • Dauphine Hands: A wide, tapered hand with a facet at the center running the length of the hand.
  • Luminous Hands: Hands made of skeleton form with the opening filled by a luminous material.
  • Skeleton Hands: Cut-out hands showing only the frame.

Hard metal
A scratch-resistant metal comprised of binding several materials, including titanium and tungsten-carbide, which are then pressed into an extremely hard metal and polished with diamond powder to add brilliance.

Helium Escape Valve
A Decompression System allowing helium to escape from inside the watch. Used by professional divers in decompression chambers.

The science of time measurement, including the art of designing and constructing timepieces.

Hourly time signal
Single beep/chime which indicates the hour, every hour when it is engaged.

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Synthetic sapphires or rubies that act as bearings for gears of a mechanical watch. A quality hand wound or automatic mechanical watch contains at least 17 jewels.


The leather loops on a leather watch strap which keeps the end of the strap in place once it has been fastened.

Seiko Kinetic® watches run entirely on self generated energy from natural movement of your wrist. It never needs a battery, being independent of conventional storage batteries.


Liquid-crystal display.

Lighted dials
Several types of lighted dials are used so that you can tell time in the dark.

Projections at either side of the case where the bracelet or strap is attached.

Lumi Brite
Environmentally safe illumination technology that will glow brightly for hours without pushing a button or drawing energy from a battery.

Self illuminating paint used on hands and markers.


A hand-wound mechanical watch.

Mechanical movement
A movement based on a mainspring which is wound by hand; when wound, it slowly unwinds the spring in an even motion.
Mechanical kinetic watches require no winding because of the rotor, which winds the mainspring every time you move your body.

Mineral glass
Hardened watch glass (or crystal) that is scratch resistant.

Minute repeater
A complication on a watch that can strike the time in hours, quarters, or seconds by means of a push button.

Moon phase
An indicator that keeps track of the phases of the moon through an aperture on the watch dial.

Iridescent, milky interior shell of the fresh water mollusk that is sliced thin and used on watch dials. While most have a milky white luster, mother-of-pearl also comes in other colors such as silvery gray, gray blue, pink, and salmon.

The inner workings or assembly that make up the main timekeeping mechanism of the watch.Mmovements are either quartz or mechanical.

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A type of calendar that automatically adjusts for months of different lengths and indicates February 29 in each leap year until the year 2100.

One of the rarest precious metals, platinum is also one of the strongest and heaviest, making it a popular choice for setting gemstone jewelry and watches. It has a rich, white luster, and an understated look. Platinum is hypoallergenic and tarnish resistant. Platinum used in jewelry and watches is at least 85 to 95 percent pure. Many platinum watches are produced in limited editions due to the expense and rarity of the metal.

Power cell
Another term for battery.

Power reserve
The time the watch will run from being fully charged. For mechanical watches it is usually 44 hours. For quartz watches it can vary from 18 months to 10 years.

Promaster watches undergo rigorous safety tests and fulfil the stringent quality standards on water and shock resistance, visibility and strap strength, as determined by the International Organisation for Standardisation (ISO 6425).

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When activated by a battery or solar power, a thin sliver of crystal very predictably vibrates, providing very accurate timekeeping.


Ratchet / Rotating bezel ring
A bezel ring which can either turn one way (counter clockwise) or both ways and generally clicks into place. Different types of rotating bezels perform different functions

Rotary ReversibleTM
A complicated case design with a practical raison d'etre, (first and famously invented by Jaeger le Coultre to protect the glass and dial from damage on the polo field or hunting field) where the case can be reversed so that the case back is uppermost.



Sapplex Crystal
Combination of sapphire and hardlex crystals.

Transparent synthetic sapphire is used for scratch-proof watch glasses as it has a hardness second only to diamond.

Screw down locking crown
Watches which are water resistant for 100m and above have screw down crowns to prevent moisture entering the case.

Synthetic gaskets that seal the joints between parts of the case and keep out the wet.

Spring devices in balance-wheel bearings that divert shocks away from the fragile pivot and allow the balance-wheel to return to its original position after shocks. If shock resistance is specified on a watch case, a watch can withstand normal wear and tear, even during strenuous sport activities.

Skeleton case
A transparent front or back that permits viewing into the inner workings of the watch.

Slide rule bezel
A rotating bezel that is printed with a logarithmic scale and assorted other scales to perform general mathematical calculations or navigational computations.

Solar Cell
Seiko Eco-Drive watches use a microns thin disc of amorphus Silicon under the dial to convert light energy into electrical energy through the photovoltaic process. The electrical energy is then stored in a rechargeable battery.

A type of quartz movement where the batteries are recharged via solar panels on the watch face. They have a power reserve so they can run even in the dark.

Solid End Links (SEL)
On some recent Rolex watches they have solid links on the bracelet.

Solid State
A watch with no moving parts. All digital watches are 100% solid state, whilst analog watches combine solid state circuits with moving parts.

Measures the elapsed time of a certain moment of an event. A second chronograph that runs concurrently with the first but can be stopped independently to record an intermediate time. It the catches up to run with the first hand again.

Spring Bar
A metal pin, telescopic in design is used on most strap designs to fasten them to the watch case. The spring bar slots into the lugs of a watch case.

The band that holds the watch to the wrist. All Rotary watch straps are made from plain leather which is then embossed or printed with patterns to imitate animal skins.

A small dial found within the main face of a watch that is used for any of several purposes, such as keeping track of elapsed minutes or hours on a chronograph or indicating the date.

Sun/moon indicator
A wheel on a watch partially visible through a cut-out window indicating a sun and moon on a 24-hour basis.

Super accurate
Using a patented integrated circuit technology, some watches are cpapble of assuring their accuracy up to 20 times more accurate than conventional quartz watches, being accurate to ±10 seconds per year.

Sweep seconds-hand
A seconds-hand mounted in the center of the dial instead of a subdial.

Swiss Made
In order to qualify as "Swiss Made" a watch must have been assembled, adjusted and subjected to official tests in Switzerland. At least 50% of the value of all parts, and its movement must have been made in Switzerland.



Tachymeter (also tachometer)
A watch function that measures the speed at which the wearer traveled by means of a numeric scale on the watch bezel of a chronograph. Frequently used to determine a speed of a car over a measured distance.

Tank watch
A particular desing of watch with heavier bars on either side of the dial, inspired by the tank tracks of World War I and first created by Louis Cartier

A watch function that enables the distance of an object from the wearer to be measured by timing how long it takes sound to travel that distance. Like a tachymeter, a telemeter consists of a stopwatch function and a special scale on the dial of a chronograph.

The "space age" metal, often with a silvery-gray appearance. It is 30% stronger and nearly 50% lighter than steel, making it ideal for watch making, especially sport watch styles. Its resistance to salt water corrosion makes it particularly useful in diver's watches.

Tonneau watch
A watch with a barrel-shaped case with two convex sides.

A device in some mechanical watches that eliminates timekeeping errors caused by slight variations due to shifts in gravity when a watch changes position during use. The round carriage or "cage" of the tourbillon holds the mechanisms that rotate the wheels, and thus the hands of the watch, in a continuous rate of once per minute.

24-hour indicator
Displays military time by sub-wheels or digital readout.







An illegal and misused term: No watch is fully 100 percent waterproof.

Water resistant
Water resistence informs the user as the the durability of the watch when put into contact with water. Water resistance is indicated in various methods. Sometimes water-resistance is measured in atmospheres (ATM), which is equal to 10 meters of water pressure or 1 bar.

Watches come in different water resistant depths and diver's depths:

  • Water resistant: Will withstand splashes of water or rain but should not be worn while swimming or diving.
  • Water tested to 50 meters: 5ATM: 5bar: Suitable for showering or swimming in shallow water.
  • Water tested to 100 meters: 10ATM: 10bar: Suitable for swimming or snorkeling.
  • Water tested to 150 meters: 15ATM: 15bar: Suitable for snorkeling.
  • Water tested to 200 meters: 20ATM: 20bar: Suitable for skin diving.
  • Diver's to 150 meters—Meets ISO Standards and is suitable for scuba diving.
  • Diver's to 200 meters—Meets ISO Standards and is suitable for scuba diving.

White On
An analog watch that is able to display digital functions at the touch of a button. An easily legible white numeric display appears on the inside surface of the crystal when any digital function is activated.

World timers
A watch with a dial that indicates up to 24 time zones around the world, usually found on the outer edge of the face or sometimes on the bezel. Time zones around the world are indicated by major cities.