Watch Terms Glossary
Watch glossary of termsIndex
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
An acrylic crystal is a plastic composite that is generally less expensive and less durable than a sapphire or a mineral crystal. The advantages of an acrylic crystal are that it flexes rather than shatters on impact. It also produces little glare under bright light and scratches can be polished out. They are also called Hesolite or Hardlex.
A function on the watch that makes a sound or vibrates at a preset time.
A function that provides altitude by responding to changes in barometric pressure, this is a feature commonly found in pilots watches.
A watch that shows the time by means of hands (analogue display) as well as by numbers (a digital display). The analogue display has a traditional dial with hour, minute and sometimes second hands. The digital display shows the time numerically or has some other functions with a liquid crystal display (LCD).
A watch showing the day, date month and 24 hours, adjusting automatically for short and long months. The calendar needs setting only once a year - at the end of February to the 1st of March.
Automatic Movement / Winding - also called self-winding
This is a mechanical watch that is wound by the movement of the wearers wrist whilst being worn as opposed to a manual mechanical. As the wearer moves their wrist , a weighted rotor turns and winds the watches mainspring. Usually most manufacturers have a a crystal skeleton case back to enable you to see this function in action. Automatic watches generally have up to 36 hours of power reserve. If an automatic watch is not worn for a period of a few days it will wind itself down and it will need to be wound by hand to get it started again.
Auto Repeat Countdown Timer
A countdown timer that resets itself as soon as the preset time has elapsed and starts the countdown again. It repeats the countdown continuously until the wearer pushes the stop button.
Battery EOL Indicator
Battery End Of Life indicator. This function warns the wearer of impending battery failure in a quartz watch by means of the second hand jumping in two or sometimes four-second intervals.
For quartz watches this is the approximate indication of the time that the battery will continue to provide power to run the watch. The battery life begins at the point when the factory initially installs the battery in the watch so the battery level may vary depending on the watch you buy. Normally the manufacturers warranty does not cover for battery life.
This is a term for quartz hybrid watch powered by a rotor inside the back of the mechanism. Electricity is generated from the rotors movement which is stored in a capacitor or rechargeable battery like a mechanical automatic watch but with the accuracy of a quartz watch. Also known under various marketing names, including Kinetic (Seiko), Omega-matic (Omega), and Auto quartz (Invicta).
Generally refers to the upper top part of the watch body around the dial . Specifically it refers to the metal ring around the outside of the crystal . On sports watches the bezel may have calibrated markings and the ability to rotate in one or two directions. On divers watches the bezel is usually calibrated into a period of 60 minutes.
A bracelet is the metal band that goes around the wearers wrist. If made of flexible separate links then these can usually be removed to change the length of the bracelet (We suggest you go to a suitable watch repair shop where they will do this for a small charge). Bracelets can be made of stainless steel, sterling silver, gold, titanium or a combination of these. See also strap .
The calendar function on a watch can refer to simply only showing the date in a cut-out window through to a more complicated triple calendar showing the date, day and month. A combination of dial cut outs and pointer hands may be used. The most complicated calendar mechanisms may be mechanically programmed to show the year and months including those with less that 31 days; leap years can also be mechanically allowed for, this is referred to as a perpetual calendar.
A term often used by Swiss watchmakers to denote a particular model type, such as Caliber 48 meaning model 48. More commonly, the term is used to indicate the movements shape, layout or size
A multifunction sport watch with a stopwatch function. Most have two or three sub dials, or mini dials, for measuring minutes and hours. When used in conjunction with specialized scales on the watch dial it can perform many different functions, such as determining speed or distance ( see tachymetre). Some can time more than one event at a time (see flyback hand and split seconds hand).
This term refers to a precision watch that is tested in various temperatures and positions, thus meeting the accuracy standards set by C.O.S.C. in Switzerland . These watches are provided with a chronometer certificate with a unique test number detailing specific test results by the C.O.S.C.
Control Officile Suisse de Chronometers or Swiss Controle Officiel des Chronometers- the independent Swiss regulatory organization that rigorously tests and certifies (or fails) watch movements for chronometer status.
A function that lets the wearer keep track of how much of a preset period of time has elapsed. Some countdown timers sound a warning signal a few seconds before the time runs out.
The crown is sometimes referred to as the winding crown or winder is usually a round piece of metal on on the right hand side of the case. It is used for winding the watch in the case of a non-automatic, for setting the hands to the correct time and for setting the date in the case of calendar equipped watches. On diving/sports models the crown may be screw-down whereby it screws onto a threaded tube to ensure the watch provides higher levels of water resistance.
The transparent cover over the watch dial is called the crystal. There are three types of crystals commonly used in watches:
- Acrylic crystal is an inexpensive plastic that allows shallow scratches to be buffed out.
- Mineral crystal is composed of several elements that are heat-treated to create an unusual hardness that aids in resisting scratches.
- Sapphire crystal is the most expensive and durable, approximately three times harder than mineral crystals and 20 times harder than acrylic crystals. A non-reflective coating on some models prevents glare in bright conditions.
Crystal Skeleton Case back
This watch will feature a case back made of a transparent material such as hardened mineral crystal or sapphire crystal that allows you to view the intricate movement of the watch from the back.
A watch that indicates the date as well as which the day of the week.
The dial is also referred to as the face, is the visible area of the watch that tells the time. It is usually marked with numbers or indices to which the hands point in order for the wearer to tell the correct time. In luxury watches, the hour markers and any surface details are hand-applied as separate elements. A technique known as Guilloché can be applied to the dial in which a pattern is etched into the dial then enamel is applied to the dial in several stages. Less expensive watches will have the numerals or indices printed onto them.
The display of time in numbers instead of hands on the dial. The numbers can appear in an LCD (Liquid Crystal Display), which shows a continuous reading or an LED (Light-Emitting Diode), which shows the time at the push of a button.
Indication of time or other data, either by means of hands moving over a dial ( analogue display ) or by means of numerals appearing in one or more windows ( digital or numerical display ); these numerals may be completed by alphabetical indications (alphanumerical display) or by signs of any other kind. Example: 12.05 MO 12.3 = 12 hours, 5 minutes, Monday 12th March. Such displays can be obtained by mechanical or electronic means.
Dual Time/Second Time Zone GMT Function
A watch which can be used to display a separate time zone distinct from that shown on the main dial. Usually the second time zone will be indicated as a 24 hour clock
One of the leading manufacturers of watch movements based in Switzerland. ETA movements are used by many major Swiss watch brands
An additional hand on a chronograph which moves with the second hand but, can be stopped independently to measure an interval which can then "fly back" to catch up with the other hand. This is useful for capturing lap times without losing the ability to capture the finish time.
A rubber or plastic ring that seals the internal works of the watch against dust, moisture and water.
It is important to have the gaskets checked at least every two years to maintain the water resistance of the watch. If your watch is used inder water frequently then a annual water resistance check is recommended
An application of 18k gold over the surface of watch case (watches will gold-plating will be usually made of stainless steel).
Gold, Rose Gold, Yellow Gold, and White Gold:
The only natural form of gold is yellow gold. Since pure 24k gold is too soft to make jewellery, it is normally made into an alloy by mixing it with other metals. The portion of pure gold to other metals determines the Karat rating. 24K is pure gold whilst 18K is 75% pure. The exact nature of the other metals used determines the color. A moderate amount of copper in the alloy creates Rose Gold. A moderate amount of palladium and nickel creates white gold.
A method of engraving a pattern in continuous decoration an engine-turned lathe and then covered with translucent enamel so that the engraving can be seen through the enamel
Hand winding (Manual Mechanical)
A watch with a manual mechanical movement which needs to be wound daily using the winding crown. This winds the mainspring up which then releases its energy to power the watch.
Helium escape valve
Before re-surfacing from diving at great depths in a pressurised enclosure, such as a diving bell, toxic gases that have been formed in the enclosure are removed and helium is mixed into the air. The helium molecules are much smaller than air and can seep into the internals of the watch. When the pressurised enclosure surfaces and is depressurised, any helium that is built up inside the case can cause the crystal on the watch to pop out of the case due to the internal pressure that has built up. This can be avoided by opening the Helium Escape Valve on the watch whilst resurfacing.
This refers to the synthetic rubies which act as bearings, end stones or pallets that are used for reducing friction within the movement of a watch. It is also important to understand that more jewels does not necessarily make a better or more accurate watch.
Karat or K
An indication of the purity of the metal used, expressed in the number of 1/24th of the pure metal used in the alloy. Metals such as gold are too soft in their pure state use in jewelry, so they are typically made into an alloy with other metals for strength. 24K (equal to 24/24ths) is pure metal. 18K is 18 parts pure metal mixed with 6 parts of other metals. That translates to 18/24=0.750, which is 75% pure, or 750 parts per thousand.
Refers to the Seiko line of Kinetic watches. This innovative technology is quartz hybrid movement that uses a battery that recharges itself using the motion of the wearers wrist. Movement of the wearers wrist charges a very efficient capacitor which powers the quartz movement. Once the capacitor is fully charged the gents models will store energy for 7-14 days without being worn. Ladies models store energy for 3-7 days. The watch alerts you to a battery charge when the seconds hand starts to move in two second intervals.
LCD Display (Liquid Crystal Display)
A digital watch display that shows the time electronically by means of a liquid held in a thin layer between two transparent plates. Followed from the earlier LED or Light Emitting Diode display of the first quartz digital watches. The LCD was preferred as it used vastly less power than the LED thus the time could be shown constantly as opposed to having to press a button for time display.
Limited Edition Watch
A watch manufactured in a specific amount often individually numbered and available only in limited quantities worldwide. Limited editions are available from most fine watch manufacturers and often come with special packaging.
Refers to a watch with a manual mechanical movement, which needs to be wound daily by the wearer using the winding crown. This winds the mainspring up which then releases its energy to power the watch.
A movement based on a mainspring which when wound slowly unwinds the spring in an even motion to provide accurate timekeeping. This watch contains many high-precision parts
Found on the Tissot T-Touch series, this calculates the atmospheric pressure which is indicated in the digital display in hPa (hektoPascal). The position of the hands indicates a barometric trend: Minutes before the hour mean that there is a drop in pressure, minutes after the hour indicate an increase. This trend is calculated from barometric pressure readings over the past eight hours which the T-Touch performs automatically
A complication on a watch that can strike the time in hours, quarters, or seconds by means of a push piece.
A complication on a watch which indicates of the phases of the moon. A regular rotation of the moon is once around the earth every 29 days, 12 hours and 44 minutes. Once set, the moon phase indicator accurately displays the phase of the moon.
The iridescent milky interior shell of the freshwater mollusc that is sliced thin and used on watch dials. Most will have a milky white luster but other colours such as silvery grey, grey blue, pink and black are available
The means by which a watch keeps time or performs its functions. There are four types of movement:
- A watch with mechanical movement uses a spinning balance wheel powered by a tightly wound spring. The watch must be wound daily using the crown
- All mechanical watches that are powered by the movement of the wearers wrist during normal usage are called automatic movement.
- A watch with quartz movement measures the vibrations in a piece of quartz and is powered by a battery.
- New hybrid watches with a non-replaceable capacitor/battery that use the movement of the wearers wrist to recharge itself are called battery less quartz. An example of this technology is used in the Seiko Kinetic series watches
A calendar complication that adjusts automatically to account for different lengths of the month (28, 30 or 31 days) and leap years. Perpetual calendars can be powered by quartz or mechanical movements and are programmed to be accurate until the year 2100 (including leap years).
This is one of the most precious metals in the world. Platinum also is one of the strongest and heaviest making it a popular choice for setting gemstone jewelry and high value luxury watches. Platinum is also hypoallergenic and tarnish resistant.
A Button that is pressed to work a function on the watch. Push-pieces are commonly found on chronographs and alarms. Caution must be advised as not to push any buttons underwater as they are not usually designed to operate underwater so this may let water into the internals of the watch
This is a type of movement that uses the vibrations of a tiny quartz crystal to maintain timing accuracy. The power comes from a battery that must be replaced about every 2-3 years in standard quartz watches.
Another name for a subdial this is usually a dial within the main dial of a watch. The best example is possibly a chronograph where there may be registers for the chronograph minutes and hours. Some watches have registers with pointers showing the day and date.
Used to describe a pointer hand on a watch dial (often a subdial), which returns to zero at the end of a prescribed period. For example a watch may have retrograde date - in this case the hand moves up a scale a day at a time, pointing to the current date - when it reaches 31 it will spring back to 1
The part of a self-winding watch that winds the movements mainspring in an automatic watch or quartz-hyrbid watch. It is a flat piece of metal, usually shaped like a semicircle, which swivels on a pivot with the motion of the wearers arm.
This term refers to a movement wound by the motion of the wearers wrist rather than through turning the winding stem (manual mechanical). In response to this motion, a rotor turns and winds the watch's mainspring. Most automatic watches have up to 36 hours of power reserve. If an automatic mechanical watch is not worn for a day or two, it will wind down and need to be wound by hand to get it started again.
A watches ability to withstand an impact from varying levels of height
A feature on a chronograph that actually is two hands, one a fly back, the other a regular hand. To time laps or different finishing times, the wearer can stop the fly backhand independently while the regular hand keeps moving.
An extremely durable metal alloy that is virtually immune to rust, discoloration and corrosion.
Swiss A.O.S.C. (Certificate of Origin)
A mark identifying a watch that is assembled in Switzerland with components of Swiss origin.
A function for measuring average speed or units. In watch making, a timer or chronograph with a graduated dial on which speed can be read off in kilometers per hour or some other unit.
A hard metal having a silver-grey appearance similar to stainless steel but it is 30 percent stronger and nearly 50 percent lighter than steel. It has high resistance to salt water corrosion so it makes it particularly useful in diver's watches. Titanium is also hypoallergenic.
Unidirectional Rotating Bezel
This is a type of elapsed time rotating bezel, often found on divers watches that moves only in a counterclockwise direction. This is a safety feature for a diver so that if they accidentally move the bezel off its original position they cannot underestimate their remaining air supply. They can be ratcheted so that they lock into place for greater safety.
The term water resistance refers to the watches ability to withstand water to certain pressures in laboratory conditions. If you dive into a pool then the pressure may well exceed the depth you are diving into.
| Swimming, Snorkeling,
|Professional Deep Sea Diving||
* Only watches marked "Divers" on the dial should be used for diving, as they fully comply with the international standards for divers watches.
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