The A-Z of watches

A

AUTOMATIC Also known as self-winding, where the physical movement of the wearer's wrist winds the movement.

B

BEZEL The ring surrounding a watch's dial. Rotating versions have markings to indicate time zones, elapsed time or other functions.

C

CALIBRE Used as a term to describe and identify a watch's basic movement, eg ‘Breitling Calibre B01'.

CHRONOGRAPH A wristwatch that also includes stopwatch functions, to mark intervals of time.

CHRONOMETER A watch that has been fully tested at Contrôle Officiel Suisse des Chronomètres (COSC) to ensure its timekeeping according to tests for temperature, position, etc.

COMPLICATION Any function found on a watch beyond telling the hours, minutes and seconds eg date, moon phase, minute repeater.

D

DIVING WATCH A watch specially designed to survive long periods immersed in water, while also indicating elapsed or remaining time to tell divers how much of their air supply remains. Life-saving stuff...

F

FLYBACK A type of chronograph that instantly restarts timing when the hand is reset to zero.

G

GMT A watch able to show time in two or more time zones (not just Greenwich Mean Time after which this sort of watch is named).

M

MANUAL WINDING The watch has to be wound by hand, via the crown (usually found next to the 3 o'clock position), typically once a day.

MANUFACTURE Always pronounced with comedic French accent; it means a watch company that makes its own movements.

MOON PHASE Device that shows the phases of the Moon; only of real use to sailors and werewolves.

N

NOVELTY Swiss abuse of English. In watch parlance a brand-new model, though often - ironically - mere novelties in the English sense.

P

PERPETUAL CALENDAR A function that shows weekday, date, month as well as leap years.

PILOT'S WATCH Usually oversized, because they're designed for maximum legibility. Can also feature a chronograph and/or GMT functions. For time in the sky.

POWER RESERVE A device that shows how much time a watch will run before it needs to be wound again.

Q

Quartz Instead of a mechanical ‘motor' powered by a spring, the resonant frequency of a quartz crystal - usually 32,768Hz - is used to regulate a battery-powered (or sometimes solar-powered) oscillator.

R

REPEATER A watch able to indicate the time via chimes, the most desirable being minute repeaters - originally developed so you could tell the time in complete darkness.

T

TOURBILLON A rotating cage containing the balance wheel, devised to counter the effects of gravity on pocket watches. Tricky to build, so found only in costly models.

TRIPLE CALENDAR A watch able to display the day, date and month.

W

WORLD TIMER Like a GMT (see G), but able to show all 24 time zones, with names of cities from each zone often featured.