ALARM WATCH
A watch provided with a movement capable of releasing an acoustic sound at the time set. A second crown is dedicated to the winding, setting and release of the striking-work; an additional center hand indicates the time set. The section of the movement dedicated to the alarm device is made up by a series of wheels linked with the barrel, an escapement and a hammer striking a gong or bell. Works much like a normal alarm clock.

AMPLITUDE
Maximum angle by which a balance or pendulum wings from its rest position.

ANALOG or ANALOGUE
A watch displaying time indications by means of hands.

ANNUAL CALENDAR
The automatic allowances for the different lengths of each month of a year in the calendar module of a watch.  This type of watch usually shows the month and date, and sometimes the day of the week (like this one by Patek Philippe) and the phases of the moon.

ANTIMAGNETIC

Said of a watch whose movement is not influenced by electromagnetic fields that could cause two or more windings of the balancespring to stick to each other, consequently accelerating the rate of the watch. This effect is obtained by adopting metal alloys (e.g Nivarox) resisting magnetization. Mechanical movements are easily influenced by the magnetic fields often found in common everyday places. This problem is generally solved by the use of anti- or nonmagnetic components in the movement.

ANTIREFLECTION, ANTIREFLECTIVE

A film created by steaming the crystal to elminate light reflection and improve legibility. Better results are obtained if both sides are treated, but in order to avoid scratches on the upper layer, the treatment of the inner surface is preferred.

ARBOR
Bearing element of a gear or balance, whose end -- called pivots -- run in jewel holes or brass bushings.

AUTOMATIC (or self-winding)
A mechanical watch which does not need to be wound by hand. The movement of the wearer activates a weight which winds the mainspring. A rotating weight, set into motion by moving the wrist, winds the spring barrel via the gear train of a mechanical watch movement.

AUTOMATON
Figures, placed on the dial or case of watches, provided with parts of the body or other elements moving at the same time as the sonnerie strikes. The moving parts are linked, through an aperture on the dial or caseback, with the sonnerie hammers striking a gong.