Watch Glossary
1356 horological terms explained · 8/23
Horizontal dial-facing-up position used in timing measurement.
Mechanism mechanically adding or subtracting time from two different sources to derive a third function.
Mechanical display of time using numerals in windows rather than traditional hands.
Escapement design delivering impulse directly to the balance wheel, reducing energy loss.
Precision polishing preventing surface warping or reflection distortion
Leather deliberately treated to appear worn, aged, or used for vintage aesthetic
Rotating bezel with markings for underwater timing and decompression
Watches combining traditional timekeeping with electronic dive computer functions.
Water-resistant timepiece rated for underwater use, featuring rotating bezel and luminous markers.
Expandable bracelet segment or strap allowing watch to fit over wet suit.
Specialized dive watch meeting ISO standards for underwater use and decompression safety.
Rotating bezel with timing marks for underwater use, typically unidirectional for safety during dives.
Extending bracelet or strap designed to fit over wetsuits or thick clothing
Diamond-Like Carbon coating providing extreme hardness and scratch resistance
Specific dial variant with dot marker above 90-degree position; rare configuration.
Two gasket seals on crown and case back for improved water resistance.
Two superimposed chronograph hands allowing simultaneous timing of multiple independent events.
Two independent tourbillons rotating in opposite directions for improved chronometric performance.
Elegant timepiece designed for formal occasions, typically thin with minimalist dial and leather strap.
Lugs with holes for direct strap attachment, found on vintage military watches.
Watch with crown positioned at 3 o'clock, designed to be worn on the right wrist for left-handed operation.
Angular clearance allowing pallet fork to separate from escape wheel teeth
Two mainsprings in series, increases power reserve, common in chronograph movements like 9300
Displays two different time zones simultaneously, typically with a 24-hour hand tracking second zone.
Hybrid watch design housing analog movement beneath integrated digital sensor layer
Low-power reflective screen used in hybrid watches for extended battery life
Quick-adjust bracelet extension system allowing rapid sizing adjustment
Rolex's quick extension system allowing additional links to be added
Unfinished watch movement; semi-completed base for assembly and finishing
Unfinished watch movement blank purchased by brands for assembly and finishing
Citizen's light-powered technology using any light source to charge the watch indefinitely.
Bezel starting at zero for tracking elapsed time measurement
Dual-point electrical contact sensors measuring heart rhythm directly from wrist
Integrated cardiac rhythm sensor for health monitoring in advanced smartwatches
Electrical process coating watch components with thin layers of precious metals like gold.
Barometric pressure sensor calculating vertical ascent during hiking and stair climbing
Porcelain-like fired coating providing smooth, durable, and lustrous finish.
Terminal links connecting the bracelet directly to the watch lugs.
Visible space between bracelet end links and case lugs; increases with age.
Custom connection between bracelet and case lugs for improved aesthetics
Mechanical engraving technique creating intricate geometric patterns using a rose engine lathe.
Bezel with intricate geometric pattern created using engine-turning decorative technique
Robust three-piece link construction with solid links throughout, durable and masculine
RGB sensor detecting circadian disruption and adjusting display brightness/color temperature accordingly
Structured leather with waxy coating, rigid finish, resists water and retains shape
Moving hour hand that varies in speed to track the equation of time throughout the year.
Shows the difference between mean solar time and apparent solar time, ranging from -14 to +16 minutes.
Small pinion on escape wheel shaft that meshes with lever or pallet fork
Toothed wheel that delivers impulses to the balance wheel via pallet fork
Number of escape wheel teeth engaged per hour; defines movement speed and accuracy rating.
Mechanism that releases energy from the mainspring in precise, regulated pulses.
Energy transfer ratio from mainspring to oscillator, improved in Co-Axial and Chronergy
Close examination of escapement mechanism for wear and proper function
Toothed wheel in the escapement mechanism that interacts with the lever to release energy.
Ubiquitous workhorse movement, 38-hour reserve, automatic, reliable and affordable
Legendary chronograph movement, column wheel, 42-hour reserve, widely used by luxury brands
Generic Swiss movement manufactured by ETA SA; widely used in affordable watchmaking
Collector authentication term for reference collection maintained by reputable vintage dealers.
Auction house assessment of finishing quality and assembly precision.
Transparent or open caseback allowing view of the movement, common on mechanical and automatic watches.