Watch Terms are a language all their own, here we explain them in plain English.


Analogue Display – a watch that displays the time with hands moving along a scale of numbers for hours, minutes, and sometimes seconds, on the dial.

Aperture – a “window” or frame on a watch dial in which a watch complication is displayed, for example the date or moon phase.

Automatic – a watch that winds itself by the movement of the wearer’s wrist. A rotor that revolves inside the watch spins and winds the watch’s movement.


Bar – A reference to atmospheric pressure, which is usually indicated in meters, to show the amount of water resistance of a watch. One bar equals approximately on ATM, or atmospheric pressure. One atmosphere equals 10 meters, approximately 30 feet. A watch that is water resistant to 10 bars is resistant to 100 meters. This is especially useful in diving watches.

Barrel – The barrel of the watch holds its hairspring, which is the part of the watch that gets “wound” to power the watch. As its name suggests, it is usually shaped like a barrel.

Bezel – the metal that surrounds the watch glass on the top side of the watch. See Rotating Bezel and unidirectional bezel, below.

Bevel(ed) – a corner or edge of a watch part that has been hand-filed to soften and curve the sharp edge. Beveling is found in watches of the highest quality.


Calendar – a watch that displays the date. There are many types of calendar watches: A simple calendar shows the numerical date and needs to be adjusted on any month that does not contain 31 days. A Day-Date displays the day of the week and the numerical date. An Annual Calendar watch automatically adjusts between the 30-day and 31-day months throughout the year, however it must be readjusted in February. A Perpetual Calendar is a watch that displays the day, date, month, and year, and also adjusts on leap years to display the number of days in February.

Caliber – a term used for the movement of the watch. For example, the Rolex Submariner’s movement is the caliber 3135.

Case Back – the case back is the back cover of the watch. It can be made of metal or sapphire crystal, the latter allows for a view of the movement.

Cell – another word for battery in quartz movement watches.

Chronograph – a watch that has a timing function in addition to displaying the hour, minutes and seconds. The chronograph is a timing mechanism that can be started, stopped, and reset on demand. It does not interfere with the timekeeping of the watch, it is a separate function.

Chronometer – derived from the French chronometre, which translates to measuring time, the word is commonly used in watches to describe an especially accurate watch.

Complication – a term that refers to any watch function other than the hours, minutes and seconds.

Crown – the top of the winding column often shaped like a cushion and often grooved. The crown can be used to set the watch, wind the watch, and in some cases contain a push-button for the chronograph function.

Date – the numerical day of the month.

Day – usually refers to the day of the week, for example Tuesday.

Day-Date – a watch that displays both the day of the week and the numerical day.

Dial – the plate between the displays of the time (watch hands, date window, etc.) and the movement. Also referred to as the face.

Display – the indication of the time and/or other functions of the watch. A mechanical watch can have an Analog display, meaning the time is shown by the progressive movement of the hands. An Alphanumeric (or digital) display shows the time in numbers, or letters and numbers.

. . . more to come!