Glossary of Terms
The measure used to define water resistance. The deeper in the water the watch goes the higher the pressure, meaning the watch needs to be stronger to stay sealed. 1 ATM is equivalent to 10m.
A movement (the watches workings) that can be wound by a crown or by an oscillating weight that spins.
A small window in the dial that displays some information such as the date or the day.
The numbers that are displayed on the dial for making each hour. Arabic numerals are in 1, 2, 3, 4, 5, 6, 7, 8 and 9 form.
Anti Reflective Coating
A coating or film that is applied to the crystal (glass) of a watch that reduces the amount of reflection and thus increases visibility.
The protective ring around the edge of the watch case. Bezels are usually made from ceramic or metal. Some bezels are able to spin in one or both rotations as a timer or time zone function.
The strap of a watch that is usually made from metal linked pieces.
The hinged pin used to join two ends of the strap.
A long, thin marker to display the hours on a watch.
Caliber / Calibre
A type or model of movement.
The housing of the watches insides.
A watch that is able to be used as a stop watch in addition to its standard display. It has dials to keep track on seconds, minutes and hours.
The method of fastening a bracelet together, usually a folding system made from metal.
A movement (heart) of a watch designed by George Daniels in 1980 that reduced friction on the moving parts and need for lubrication.
The winder used to control the movement and hands from the outside of the case. It is used for setting the time, date and winding the movement.
The clear glass that allows the dial to be seen. This can be made from acrylic (typically on older watches), glass or synthetic sapphire.
A small magnifying lens that is on the crystal of the glass to magnify the date.
An extremely hardwearing, scratch resistant material that is used for watch cases.
A feature from a watch that is in addition to the normal time keeping features. This can include calendars, moon phases, alarm clocks, second time zones.
The ‘face’ of the watch that shows the time, date and other features.
A additional folding link in a bracelet that allows a watch to fit over a wetsuit without having to use tools.
A chronograph that uses two second hands simultaneously to measure split times.
A feature on the dial of a watch that displays the day and the date.
The links that connect the case to the bracelet.
A device from inside a mechanical movement that controls the timing through the rotation of the wheels and the movement of the hands. This escapement causes the ticking sound of a watch.
Usually a rubber material that is compressed between two components to make a seal.
Greenwich Mean Time. The original standard of time that all other time is calculated from.
A stamped code on precious metals to pinpoint origin and authenticity.
The indicators that travel around the watch dial to indicate the time.
A mechanical movement that needs the be wound up in order to gain power. Usually done through winding the crown.
Helium Escape Valve (HEV)
Developed by Rolex with Comex (Professional Diving Company) to release the pressure within the watch to prevent the crystal from popping off.
The science and study of the measurement of time.
Arabic numerals, Roman numerals or symbols that are placed around the dial to mark hours.
Markers on the dial to show the incremental units.
Normally Rubies or Synthetic that act as a bearing, with high wear resistance and low friction properties.
Part of the case to which the strap or bracelet attaches.
The visible glow of a dial. Usually put on with pain but traditionally made with radioactive materials.
A brand of luminous paint that is non-radioactive.
A mechanical movement, it requires a crown to be wound to power it.
The heart of a watch. It powers the watch.
An indicator to show the amount of energy that can be stored before the movement needs winding etc.
A button(s) on the side of watches case that starts, stops and resets a chronograph.
A natural material, taken from within the earth. It produces oscillations that are used with an electrical impulse to measure time.
The adjustment of the watches movement to improve accuracy of the watches time reading.
Screw Down Crown
A crown that creates a seal between itself and the case by screwing down on to the case.
A band that attaches the watch to a wrist.
A brand of luminous paint that is non-radioactive.
The movement of the second hand that moves in a smooth way rather than in a traditional ticking.
A extremely hard synthetic material that is used to make watch glass.
A watch can only be considered to be Swiss made if, (1) its movement is Swiss; (2) its movement is cased up in Switzerland and (3) the manufacturer carries out the final inspection in Switzerland.
A movement where some of the casing has been removed and cut away so that the working parts can be seen.
A small dial on the main dial of a watch that displays an additional function.
A means of converting elapsed time (in seconds per unit) to rate (in units per hour).
The ability to keep the inside of a watch dry when in water. This is measured in ATM
The action used to tighten the main spring and power the watch.
A box or mechanism that keeps an automatic watch wound when it isn’t being worn.