A
- Anglage
- Beveling and polishing the edges of watch movement components to create smooth, reflective borders.
- Angleur
- A specialist who bevels and polishes the edges of watch movement components.
- Automatic watch
- A mechanical watch, with no battery, whose mainspring is wound by a weighted rotor that turns as the wearer moves.
B
- Balance spring
- The fine spring that returns a mechanical watch's balance wheel toward its resting position and helps determine its oscillation rate.
- Black polishing
- Polishing a metal surface so flat and smooth that it appears mirror-bright or black depending on the viewing angle.
C
- Caliber
- A watch's internal movement, or the designation identifying a particular movement design.
- Casing-up
- Installing and securing the assembled watch movement, dial and hands inside the case.
- Chronograph
- A watch with a stopwatch function that can start, stop and reset elapsed-time measurement while continuing to tell the time.
- Complication
- A watch function beyond displaying hours, minutes and seconds, such as a calendar, chronograph or second time zone.
- COSC
- The Contrôle Officiel Suisse des Chronomètres, the Swiss body that tests watch movements and certifies those that pass as chronometers.
- Côtes de Genève
- A decorative finish of regular bands applied with an abrasive tool to watch movement surfaces, often plates and bridges.
D
- Décolletage
- Producing small precision components from metal bar stock on an automatic lathe, using turning and related machining operations.
E
- Engraving
- Cutting a design or lettering into metal or another hard material, by hand with a graver or by machine or laser.
- Escapement
- The mechanism that releases a mechanical watch's gear train in controlled steps and delivers energy to the balance.
G
- GMT watch
- A watch that shows a second time zone, usually with an extra hour hand that turns once in 24 hours against a 24-hour scale.
- Guilloché
- A decorative pattern of repeated engraved lines, traditionally cut into metal with a hand-operated engine-turning machine.
- Guillocheur
- A craftsperson who engraves repeating decorative patterns on watch dials or other metal surfaces using a hand-operated engine-turning machine.
H
- Haute horlogerie
- French for fine watchmaking: the upper end of the trade, judged by how movements are made and finished, by design and by service.
- Horology
- The study and practice of measuring time and making timepieces.
M
- Mechanical watch
- A watch powered by a wound spring rather than a battery, its rate set by an oscillating balance wheel and balance spring.
- Métiers d’art
- French for skilled artistic crafts, including disciplines such as embroidery, engraving and decorative metalwork.
- Movement assembly
- Fitting together and lubricating a watch's internal components so its mechanism can run and be tested.
P
- Perlage
- A decorative finish of small, overlapping circular marks applied to watch movement plates and bridges with a rotating abrasive tool.
Q
- Quartz watch
- A battery-powered watch whose rate is set by a quartz crystal vibrating 32,768 times a second, counted down electronically to drive the hands.
R
- Regulation
- Adjusting a mechanical watch's running rate to reduce how much time it gains or loses.
- Rhabilleur
- French for a watch repairer who diagnoses faults and restores watches to working order.
T
- Tourbillon
- A mechanism that rotates the balance and escapement in a cage to average out gravity-related timing errors in vertical positions.
W
- Watch finisher
- A specialist who prepares and finishes watch components by removing surface defects, polishing or applying decorative textures.
- Watchmaker
- A specialist who assembles, adjusts, services or repairs watches and their movements.
