Watch Glossary
1676 horological terms explained
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
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
Measurement tracking point-contact wear rate on equation marchante cam surface
Moving hour hand that varies in speed to track the equation of time throughout the year.
Pre-manufactured eccentric gear blank requiring precision grinding to equation profile
Quality assurance procedure verifying eccentric gear dimensional accuracy pre-grinding
Shows the difference between mean solar time and apparent solar time, ranging from -14 to +16 minutes.
Precisely contoured mechanical cam encoding solar-sidereal time differential throughout year
Measurement quantifying friction losses in equation marchante cam follower mechanism
Precision grinding fixture ensuring consistent equation of time cam profile accuracy
Precision specification for equation of time disc curvature deviation acceptance
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.
Collector term for verification of maker's hand-executed dial markings, scratches, and imperfections.
Transparent or open caseback allowing view of the movement, common on mechanical and automatic watches.
Explorer II with white dial, resembling polar ice fields, reference 16570.
Auction documentation extracted from original manufacture archives confirming watch production details.