Terminology
Watch Parts
Bezel: The ring surrounding the watch crystal, often used to hold the crystal in place. In some watches (e.g., dive watches), the bezel is rotatable and used to track time.
Bracelet: The metal band that secures the watch to the wrist, often made of stainless steel, titanium, or precious metals.
Buckle: The clasp used to secure the watch strap or bracelet. Common types include pin buckle, deployant, or fold-over clasps.
Caliber (Movement): The internal mechanism that drives the hands and complications of the watch. It can be mechanical, quartz, or automatic.
Case: The housing that contains the movement, dial, and other internal parts of the watch. It can be made of various materials like steel, gold, titanium, or ceramic.
Crown: The small knob on the side of the case used to set the time, wind the watch, or adjust other functions (e.g., date).
Crystal: The transparent cover over the dial, typically made from sapphire, mineral glass, or acrylic.
Dial: The face of the watch where the time is displayed, often featuring indices, numerals, and complications.
Hands: The arms on the dial that indicate time (hour, minute, and seconds hands). Some watches have additional hands for complications.
Indices: The markers on the dial that indicate the hours or minutes.
Lugs: The projections on the case where the strap or bracelet is attached.
Rotor: In automatic watches, the weighted piece that moves with wrist motion to wind the mainspring.
Mainspring: A coiled spring in mechanical watches that stores energy to power the movement.
Subdial: A smaller dial set within the main dial that shows additional information like seconds, chronograph functions, or date.
Balance Wheel: A rotating wheel that oscillates back and forth to regulate the timing in mechanical watches.
Escapement: The mechanism that transfers energy from the mainspring to the gear train and regulates the movement.
Gasket: A seal used in the case, crystal, or crown to prevent water or dust from entering the watch.
Lume: A luminous material applied to the hands or indices to make them visible in the dark.
Watch Complications
Chronograph: A watch with a built-in stopwatch feature. It includes additional subdials to measure seconds, minutes, and hours.
Tachymeter: A scale on the bezel or dial used to measure speed over a known distance, often found on chronographs.
Tourbillon: A complex mechanical complication that counters the effects of gravity on the watch's accuracy by rotating the escapement.
GMT (Greenwich Mean Time): A watch complication that allows tracking of two time zones simultaneously, usually with an additional hand.
Moonphase: A complication that shows the current phase of the moon, often with a small subdial.
Perpetual Calendar: A complication that automatically accounts for leap years and varying days in months.
Annual Calendar: A complication that automatically accounts for varying days, weeks and months of the year
Power Reserve: An indicator showing the amount of energy remaining in the watch’s mainspring.
Minute Repeater: A complication that chimes the hours, quarter-hours, and minutes on demand.
Day/Date Function: A complication that displays the current day of the week and the date on the dial.
Skeleton Watch: A watch with an open dial or transparent case back to display the internal movement.
Watch Accessories
Strap: The band made of leather, rubber, fabric, or other materials that secures the watch to the wrist.
Deployant Clasp: A fold-over clasp that allows the strap or bracelet to open up for easy wear.
NATO Strap: A fabric strap, typically made of nylon, known for its durability and military origins.
Spring Bar: A small metal bar used to attach the strap or bracelet to the watch case.
Watch Winder: A device used to keep automatic watches wound when they’re not being worn.
Watch Roll: A portable case designed to store and protect watches while traveling.
Watch Box: A box designed to hold and protect a watch collection, often featuring cushioned compartments.
Watch Tool: A tool used for removing or adjusting watch parts, such as spring bars or links.
End Links: The part of a bracelet or strap that connects to the lugs of the watch.
Watch Movement Types
Mechanical Movement: A movement powered by a wound mainspring and regulated by an escapement and balance wheel, requiring manual winding.
Automatic Movement: A type of mechanical movement that winds itself using a rotor, which moves with the wearer’s wrist motion.
Quartz Movement: A movement powered by a battery, using a quartz crystal oscillator to keep time with high accuracy.
Solar-Powered Movement: A type of quartz movement that uses solar energy to recharge a battery.
Hybrid Movement: A combination of mechanical and quartz technologies, often seen in watches with mechanical hands and digital features.
Watch Jargon & Terms
Aftermarket: Refers to non-original parts, modifications, or accessories added to a watch after purchase.
Water Resistance: The watch’s ability to resist water infiltration, measured in meters or ATM (atmospheres).
Antimagnetic: The watch's ability to resist the effects of magnetic fields, often achieved with special materials in the movement.
COSC: An acronym for "Contrôle Officiel Suisse des Chronomètres," which certifies Swiss watches that meet strict accuracy standards.
Deployant: A clasp that opens in a way that allows the watch strap to fold over itself, often used for a more secure fit.
Double Chronograph (Rattrapante): A chronograph complication that features two second hands, allowing the timing of two events simultaneously.
Horology: The science and art of timekeeping and making timepieces.
In-house Movement: A movement that is developed, designed, and manufactured by the watch brand itself, as opposed to being sourced from third parties.
Limited Edition: A watch produced in a restricted quantity, often with unique features that make it collectible.
OEM: Original Equipment Manufacturer, referring to parts or accessories made by the watch’s brand.
Oversized Watch: A large-sized watch, typically with a case diameter above 44mm.
Patina: The natural aging process that causes materials, such as metal or leather, to develop a worn or vintage look over time.
Provenance: The documented history of a watch, particularly important for vintage or collectible timepieces.
Regatta Timer: A countdown timer used in sailing races to mark the time before the start of a race.
Servicing: The maintenance process where the movement and other parts of a mechanical watch are cleaned, lubricated, and adjusted.
Superluminova: A non-radioactive luminous material applied to watch hands and indices, commonly used for modern watches.
Tonneau Case: A case shape that resembles a barrel with rounded edges, distinct from the more common round or square cases.
Unidirectional Bezel: A bezel that only rotates in one direction (counterclockwise), commonly found in dive watches to prevent accidental timing errors.
SOTC: State of the Collection
EDC: Everyday Carry