Winding Mechanism
The mechanism which tightens the mainspring in a watch.
Atmosphere (ATM)
Unit of pressure used in watch making to indicate water-resistance. One Atmosphere Pressure (1 ATM) approximately corresponds to a water depth of 10 metres.
Zalium
Zalium is an alloy of aluminium and zirconium sometimes used in watchmaking.
Bridge
A watch bridge is a watch part attached to the main plate to help form the frame of a watch movement.
Striking Mechanism
An acoustic device that automatically or on demand indicates the hour and possibly quarter-hour and minutes or sounds at a pre-set hour.
Movement
The assembly of mechanisms and other internal elements of any timepiece.
Horology
The science of time measurement including the art of designing and constructing timepieces.
Calibre
A term that indicates a kind of watch movement. Calibres come in many variations.
Annual Calendar
The automatic allowances for the different lengths of each month in the calendar module of a watch.
Barrel
Used in mechanical watches (and clocks), a barrel is a cylindrical metal box closed by a cover, with a ring of gear teeth around it, containing a spiral spring called the mainspring, which provides power to run the timepiece.
Cotes de Genève
Decoration on a dial comprising an even pattern of parallel stripes.
Marine Chronometer
Highly accurate mechanical timekeeper used for determining the longitude on board a ship.