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With this list of terminology popularly used by expert watchmakers when describing timepieces, their parts and functions
A mechanical movement that needs no winding because the automatic mechanism winds the mainspring every time the watch moves.
A watch whose mainspring is wound by the movements or accelerations of the wearer's arm. A rotor turns and transmits its energy to the spring by means of a mechanism originally invented in Switzerland in the 18th century.
This is a French word meaning a watch movement (not including the dial and hands) that is incompletely assembled.
A precision watch tested in various temperatures and positions so as to match accuracy standards set by an official Swiss institute.
A watch functions in addition to timekeeping. For example, a minute repeater chime, split-second chronograph, tourbillon (See below) or perpetual calendar.
Button on the outside of the case used to set the time and calendar. In the mechanical watches, it is also used to wind the mainspring.
A French word for a movement blank – that is to say an incomplete watch movement sold as a set of loose parts. These comprise the main plate, bridges, train, winding and setting mechanism, and regulator. However, the timing system, escapement and mainspring are not parts of the ébauche.
A mechanism that alternately checks and releases the gear train by a fixed amount and transmits a periodic impulse from the spring to the balance wheel
The visible side of the watch containing the dial. Most faces contain Arabic or Roman numerals to indicate hours. When Roman numerals are used, it is traditional to use IIII, rather than IV, to indicate 4 o'clock.
The system of gears transferring power from mainspring to escapement.
The driving spring of a watch, situated in the barrel.
A device that chimes the time when the wearer pushes a specific button.
A watch with a seconds hand that measures intervals of time. When a stopwatch is incorporated into a standard watch, both the stopwatch function and the timepiece are referred to as a ‘chronograph’.
A seconds-hand that mounted in the centre of the watch dial.
A device on a chronograph watch that measure the speed at which the wearer has travelled over a measured distance.
A device in a mechanical watch that eliminates timekeeping errors caused by the slight difference in the rates at which a watch runs in the horizontal and vertical positions. The tourbillon comprises a round carriage (or cage) holding the escapement and the balance. It rotates continuously once per minute.