Watch Glossary

Secondary dial displaying 24-hour time format instead of traditional 12-hour cycle.

Full 24-hour time scale instead of standard 12-hour format

Movement oscillating at 36,000 beats per hour, standard in chronographs for 1/10th second resolution.

Swiss-French horologist who revolutionized watchmaking with innovations like the tourbillon and Breguet spiral

Process of zeroing motion sensors to ensure accurate step counting and gesture recognition

Official document certifying watch meets specified precision standards.

Acceptable deviation from precise time, chronometer ±4-6 sec/day, standard ±15 sec/day

Using chemical acids to selectively eat into metal surfaces creating textured designs.

Machine learning system identifying exercise types from accelerometer and heart rate data

Bracelet with removable links allowing sizing to fit the wearer's wrist.

Residual luminescence visible on watch dial after primary glow has substantially faded

Display indicating days elapsed in current lunar cycle from new moon to full moon.

Académie Horlogère des Créateurs Indépendants; prestigious association of independent watchmakers

Rolex's entry-level sports watch honoring RAF pilots from 1945

Watch combining chronograph stopwatch function with mechanical alarm capability.

Mechanical mechanism that sounds an alert at a preset time, requiring a separate alarm barrel and trigger.

Mechanical striking system activating audible alert at predetermined time.

Timepiece with mechanical or electronic alarm function alerting wearer at set time.

Watch with all factory-original components including case, dial, hands, bezel, and movement

Premium reptile skin with smaller scales than crocodile, refined luxury material

American alligator leather with smaller, more uniform scales than crocodile

Genuine alligator leather with distinctive scaled texture, premium luxury option

Lightweight metal alloy used in sport watch cases and bezel inserts

Lightweight anodized aluminum bezel insert with printed scale

Photoreceptor that auto-adjusts display brightness based on surrounding conditions

Thermistor measuring environmental temperature for weather prediction applications

Maximum arc of the balance wheel's swing; indicates movement health and power reserve.

Traditional escapement design shaped like an anchor, most common in mechanical watches before lever escapements.

Beveling technique decorating edges of movement components with angled chamfers

Calendar mechanism requiring manual correction only once per year in February or March.

Calendar watch combining annual and perpetual calendar features for extended accuracy.

Complication requiring manual winding of the mainspring only once per year, storing energy for 365 days.

Electrochemical process creating protective oxide layers on aluminum watch components.

Movement shielded or constructed to resist magnetic field interference affecting timekeeping.

Optical treatment on sapphire reducing light reflection for improved dial visibility.

Protective mechanism that allows jeweled bearings to move laterally when watch experiences impact.

Watch case constructed from non-ferrous materials or soft iron shield protecting the movement.

Resistance to magnetic fields, critical in modern movements like Omega Co-Axial 8900

Timepiece designed to resist magnetic field interference using special materials and shielding.

Window or opening in dial revealing complications like date or moonphase.

Dial hour markers individually applied and set separately from dial surface for sophistication.

Metal or material indices affixed to dial surface for superior aesthetic and durability.

Standard numerical hour markers using Arabic numeral style

Main rotating axle of the barrel that connects the mainspring to the gear train.

Speed of underwater ascent; typically limited to prevent nitrogen narcosis and bends.

Strategic application of oils during movement reassembly process

Historic astronomical instrument adapted into watch form to measure celestial positions and angles.

Unbalanced case design where elements are not mirrored, creating unique visual interest and distinctiveness.

Workshop or studio where watches are crafted by skilled artisans

Atmosphere unit; 1 ATM equals approximately 10 meters of water depth.

In-house automatic, 60-hour reserve, chronometer certified, basis for Royal Oak movements

Self-winding mechanical movement powered by the wearer's wrist motion via a rotor.

Quartz-based stone with sparkling inclusions used for decorative watch dials and bezels.

Transparent caseback allowing view of the movement inside.

Bridge component that supports upper balance wheel pivot and hairspring stud

Oscillating wheel that regulates timekeeping by vibrating at a constant frequency.

Cleaning, inspection, and adjustment of balance wheel for timekeeping accuracy

Fixed pins limiting pallet fork swing to prevent excessive escape wheel engagement

Metric pressure unit; 1 bar equals approximately 10 meters of water depth.

Watches rated in bars; typical diver watches are 30 bar minimum.