Glossary - Time Boutique
Watch glossary A-Z
Watchmaking terms, curated for collectors and beginners. From anchor to certificate, iconic models, complications and workshop vocabulary. Search for a term below or jump directly to the letter.
A
- Anchor escapement · Lever escapement
- Mechanism that releases the spring's energy to the gear train in controlled impulses; the audible "tick-tock" is created as the lever pallets strike the escape wheel. The Swiss lever escapement has been the standard in mechanical watches since the mid-19th century and the basis for variants such as Omega's Co-Axial escapement.
- Aquanaut
- Patek Philippe model line, introduced in 1997 as the sportier counterpart to the more elegant Nautilus. Characteristic are the embossed dial with small rounded shapes, the tropical rubber strap and the rounded octagonal bezel. Today the Aquanaut is one of the most sought-after sports watches of all.
- ATM · Bar · Atmosphere
- Pressure unit for water resistance. 1 ATM is roughly 10 metres static. Important: ATM values are test pressures, not real dive depths; dynamic loads (swimming, diving) are higher. For regular swimming, watches should rate at least 5 ATM; for diving 20 ATM (200 m).
- Automatic watch · Automatic · Self-winding
- Mechanical watch that winds itself via a rotor turning with the wearer's arm movements and tensioning the mainspring. Concept since 1770 (Perrelet), perfected as a water-resistant wristwatch in 1931 by Rolex. Power reserve typically 38 to 72 hours; on modern calibers like Rolex 3235 or Patek 26-330 up to 80 hours.
B
- Big date · Outsize date
- Date display with two separate discs for tens and units, making it noticeably larger and more legible. Style-defining at A. Lange & Söhne (Lange 1, 1994) and now found at many manufactures, such as Glashütte Original PanoMatic or Breguet Marine.
- Bezel
- Ring around the dial that holds the crystal. Can be fixed, rotating (dive watch, unidirectional counter-clockwise), bidirectional (GMT) or fitted with a tachymeter scale (Daytona). Materials range from stainless steel and Cerachrom ceramic to gold and gem-set variants.
- Balance · Balance wheel
- Oscillating wheel in the movement whose frequency sets the watch's beat. Together with the hairspring the "heart" of the mechanical watch; modern constructions use Glucydur alloy or free regulation via timing screws ("Microstella" at Rolex, "free-sprung Gyromax" at Patek).
C
- Calatrava
- The classic dress-watch line by Patek Philippe, introduced in 1932 with reference 96. A plain round case, finely applied index dial, thin bezels, the epitome of elegant Geneva watchmaking. The Calatrava cross has been Patek Philippe's emblem since the 1880s.
- Cerachrom · Ceramic bezel
- Rolex's in-house high-performance ceramic for bezel inserts. Practically scratch-proof, colour-stable against UV and salt water, no more fading bezels. First in the GMT-Master II Cerachrom in 2005, today the standard across the Professional models such as Submariner, Daytona, Sea-Dweller and Yacht-Master.
- Chronograph · Stopwatch
- Watch with an additional stop function controlled by separate pushers. An important complication since the 19th century; famous examples: Rolex Daytona, Omega Speedmaster, AP Royal Oak Offshore, Patek Philippe 5170. Column-wheel chronographs are technically considered more demanding than cam-actuated chronographs.
- Chronometer
- Watch with an official precision certificate, usually from COSC. Strict rate accuracy requirements (−4 to +6 seconds per day) over 15 days in five positions and three temperatures. Roughly every third Swiss watch in the premium segment carries the seal; Rolex certifies every model, Omega goes one step further with Master Chronometer.
- COSC · Contrôle Officiel Suisse des Chronomètres
- Official Swiss testing body that certifies movements for chronometer status (−4 to +6 seconds per day). Grants the right to print "Chronometer" on the dial.
- Cyclops · Date lens
- Cylindrical lens that magnifies the date on a watch crystal 2.5×. A Rolex patent from 1953, a fixed feature of the Datejust, GMT-Master, Submariner Date and Day-Date. Visually one of the most unmistakable features of a Rolex.
- Caliber · Movement
- Designation of a specific movement and its specifications. Examples: Rolex 3235, Patek 26-330, ETA 2824; provides information on manufacturer, construction and feature set. "Manufacture caliber" means in-house development; "ETA caliber" or "Sellita SW200" are externally sourced movements used by many smaller brands.
- Complication
- Any function of a watch beyond plain hours and minutes, e.g. date, moonphase, chronograph, perpetual calendar, minute repeater, tourbillon. The term comes from the French "compliquer" and describes the added mechanical complexity. "Grande Complication" denotes watches with three or more classical complications, such as minute repeater, perpetual calendar and tourbillon.
- Crown
- Knurled knob on the side of the case for setting and winding the watch. On water-resistant models often screw-down; Rolex distinguishes Twinlock (two gaskets, up to 100 m) from Triplock (three gaskets, up to 1,000 m+ in Submariner, Sea-Dweller, Daytona). The crown often bears the brand logo (Rolex crown, Patek cross, Omega logo).
- Certificate · Authenticity certificate
- A written authenticity, service or chronometer attestation. At Time Boutique every watch sold comes with an authenticity certificate documenting service status, verified reference and serial number and inspection result, the basis of our warranty.
D
- Datejust
- A Rolex classic since 1945, presented for the brand's 40th anniversary. The first automatic, water-resistant chronometer watch with a date in a window, also the birthplace of the Cyclops lens (1953). Today available in case sizes 28, 31, 36 and 41 mm, in steel, bicolour (Rolesor) and precious metal.
- Daytona · Cosmograph Daytona
- Rolex chronograph since 1963, named after the Daytona Beach race track. One of the most sought-after sports watches in the world; early models with "Paul Newman" dial are pinnacle collector pieces. Since 2000 with the manufacture caliber 4130 (column-wheel chronograph with vertical clutch), since 2023 with cal. 4131.
- Day-Date · President
- Rolex model since 1956. The first watch to show the weekday spelled out in full. Traditionally in precious metal (gold, platinum) with the iconic President bracelet, a symbol of success and status, worn by heads of state, artists and CEOs.
- Dial
- Front of the watch with hour markers, logos and complication displays. Material (lacquer, enamel, aventurine, meteorite, mother-of-pearl, stone), colour and finish (soleil, guilloché, matte, gloss) significantly shape the visual character. On rare vintage pieces often the value-defining factor.
E
- Escapement · Échappement
- Mechanical heart of a watch that converts the continuous energy of the spring into regular impulses. Variants: classic lever escapement, Co-Axial (Omega/George Daniels), chronometer escapement and free-form tourbillon constructions.
- Everose
- Rolex's own rose-gold alloy (2005 patent) that retains its warm pink tone even after years thanks to a platinum content, unlike classic rose-gold alloys with pure copper that fade. Used in many Day-Date, Datejust, Sky-Dweller and Yacht-Master models.
- Explorer
- Rolex model line since 1953, launched after the first ascent of Mount Everest by Sir Edmund Hillary and Tenzing Norgay. A robust three-hand sports watch with the iconic 3-6-9 dial. Since 1971 the Explorer II adds a 24-hour hand and rotating 24-hour bezel for polar explorers and cave explorers.
F
- Folding clasp · Deployant · Deployment
- Hinged clasp on metal or leather bracelets that simplifies putting on and taking off the watch while preventing it from being dropped. Rolex Oysterlock and Easylink (with 5 mm comfort extension), Patek with the Maltese-cross logo, Cartier with the double-fold system.
G
- GMT · Greenwich Mean Time · Second time zone
- Complication to display a second time zone, often with an additional 24-hour hand and 24-hour bezel. Famous: Rolex GMT-Master, introduced 1955 for Pan-Am pilots; two-tone bezels are nicknamed Pepsi (red/blue), Coke (red/black) and Batman (black/blue).
- Guilloché
- Filigree engraved patterns on dials, traditionally produced on the "tour à guillocher", a historical lathe that only a few manufactures still operate. Characteristic of Patek Philippe, Breguet (clous de Paris, vagues, grain d'orge) and A. Lange & Söhne.
- Gear train
- Chain of fine gears that transmits energy from the barrel via the minute and second wheels to the escapement. Gear ratios determine how an unwinding spring becomes exact seconds, minutes and hours; precision mechanics with tooth flanks at micrometre tolerance.
H
- Hype watch
- Model whose market price, due to scarcity, social-media attention and collector speculation, is significantly above list short-term. Recent examples: Rolex Daytona steel, Patek Nautilus 5711, AP Royal Oak Jumbo 15202. Caveat: hype prices are volatile; what peaked in 2022 can cool sharply by 2024.
- Helium escape valve · Escape valve
- One-way valve on professional dive watches (e.g. Rolex Sea-Dweller, Omega Seamaster Diver 300M) that releases excess helium from the decompression chamber. Background: during saturation diving, helium penetrates the case; on ascent the crystal would pop out under pressure if the gas could not escape through the valve.
- Hairspring · Spiral
- Filigree spiral spring on the balance staff that creates the balance's oscillation. Material and geometry determine precision and antimagnetism; modern materials such as Rolex Parachrom (niobium-zirconium) or Patek/Ulysse Nardin silicon (Si14, Spiromax) are largely antimagnetic.
I
- Index · Hour marker
- Hour marker on the dial; can be applied (set, often in gold or white gold), printed or embossed. Shape (baton, arrow, Roman, Arabic) and material significantly influence elegance and legibility; on Patek Philippe often "bâton dauphin", on Rolex usually baton with lume dots.
- Incabloc · Shock protection
- Shock-absorbing system for the balance that protects the sensitive staff from impacts. Standard in most mechanical Swiss movements since the 1930s; Rolex uses its own variant (Paraflex), Omega the Kif system.
J
- Jubilee bracelet
- Five-piece-link bracelet introduced by Rolex in 1945 for the brand's 40th anniversary. A characteristic element of the Datejust and, since 2018, also the GMT-Master II Pepsi and Batman. Wears more supplely than the Oyster bracelet, considered slightly more elegant and less sporty.
- Jewel · Bearing jewel
- Synthetic ruby used as a bearing on staffs and gears. Reduces friction and wear. Typical movements have 17 to 31 jewels; the count on the movement is often given as a mark of quality ("31 jewels"). Very complex movements such as perpetual calendars can contain 40+ jewels.
L
- Lug · Horn
- Connecting piece between case and bracelet. Shape and length significantly influence wearing comfort and the watch's look, from the straight lug of the Submariner via the artfully curved horns of the Patek Calatrava to the integrated lugs of the Royal Oak and Nautilus.
- Leather strap
- Classic strap of calf, alligator or crocodile leather, often with hand-stitched seam. Typical for dress watches like Calatrava, Tank or Lange 1. Depending on wear frequency, should be renewed every 2 to 3 years; the service is offered free of charge at the Munich atelier.
- Limited edition
- A model with a restricted production run and numbered engraving ("01/50"), often created for an anniversary or partnership. "Limited" can mean "50 pieces worldwide" or "limited to 5,000 pieces"; rarity and collector value depend heavily on the run size. True low-volume limitations are considered the most value-stable.
- Lume · Super-LumiNova
- Phosphorescent coating on hands and indices for legibility in the dark. Today predominantly Super-LumiNova (strontium aluminate); at Rolex the in-house Chromalight (blue glow, 8 hours duration). Vintage watches often carry tritium (marked "T<25") or radium, both weakly radioactive and no longer permitted.
M
- Mainspring barrel
- Drum in the movement that contains the wound mainspring. Stores the watch's energy and releases it via the gear train to the escapement in a controlled fashion. Double barrels extend the power reserve, e.g. in Lange Saxonia or Panerai Luminor 8-Day.
- Manual winding
- A mechanical movement wound manually via the crown, a daily ritual for many enthusiasts. A classic construction often found in dress watches like the Patek Calatrava or Omega Speedmaster Professional. Without a rotor it can be built thinner; many ultra-thin movements are manual.
- Manufacture · In-house movement
- A watch house that makes essential movement components itself. Examples: Rolex, Patek Philippe, A. Lange & Söhne, Jaeger-LeCoultre, Vacheron Constantin. The term stands for vertical integration: movement construction, case, dial and often the bracelet are produced in-house.
- Master Chronometer · METAS-certified
- The strictest Swiss precision seal, awarded by the Federal Institute of Metrology (METAS). Test over 10 days in six positions, at varying temperatures and under a magnetic field of 15,000 gauss, noticeably more demanding than the COSC chronometer test. Omega Co-Axial Master Chronometer and Tudor MT calibers carry the seal.
- Milanese bracelet · Mesh
- Finely woven mesh bracelet in stainless steel, originally from Milan. Wears extremely supple and hugs the wrist, popular for summer wear. A classic element on Omega (Speedmaster and Seamaster), Breitling and many vintage Bauhaus watches such as the Junghans Max Bill.
- Minute repeater
- Acoustic complication that strikes hours, quarters and minutes on hammers and gongs at the push of a button; hours in a low tone, minutes high, quarters as a double strike. One of watchmaking's most demanding complications; every piece is tuned individually. Primarily made by Patek Philippe, Audemars Piguet and Vacheron Constantin.
- Moonphase
- Complication that displays the current moon cycle (new moon, waxing/waning moon, full moon). A classic element in dress watches and perpetual calendars. Standard moonphases drift by one day every 2.5 years; high-precision "astronomical" moonphases only after 122 years, a tour-de-force of craftsmanship.
N
- Nautilus
- Sporty-elegant Patek Philippe model line, designed in 1976 by Gerald Genta (also the creator of the Royal Oak). Distinctive octagonal bezel with rounded corners, integrated bracelet; the slogan "a watch you could wear with a wetsuit or a black tie" defined the concept. The steel reference 5711/1A became the most sought-after sports watch of all until Patek discontinued it in 2021.
- NATO strap
- One-piece fabric strap threaded through the lugs of the watch. Originally developed for the British military (Defence Standard 66-15, 1973), the watch stays on the wrist even if a spring bar breaks. Today popular as a robust and versatile strap; James Bond wore a Submariner on a black-red-green NATO in "Goldfinger".
- NOS · New old stock
- Collector term for unworn, factory-packed watches from older production runs that were never sold. NOS pieces are particularly sought after because they preserve the original state including protective films, labels and full papers, effectively a time capsule.
O
- Oscillator
- The oscillating element in the movement (usually the balance with hairspring) that sets the watch's beat. Frequency typically 2.5–5 Hz (18,000 to 36,000 half-oscillations per hour); higher frequencies give more precise seconds, lower frequencies longer power reserves. Quartz movements oscillate at 32,768 Hz.
- Oyster · Oyster case
- Water-resistant case design by Rolex, patented in 1926. Screw-down case with screw-down crown, the basis of every modern water-resistant watch. In 1927 Mercedes Gleitze wore the first Oyster on an English Channel crossing, which established the brand worldwide.
- Overhaul · Service · Full revision
- Full maintenance of a movement: disassembly, cleaning, oiling with specialist watch oils, replacement of worn parts, reassembly and fine regulation. Recommended every 5 to 10 years, value-preserving and decisive for longevity. At Time Boutique always with a documented service record.
P
- Pusher
- Buttons on the case, usually flanking the crown, for operating complications, typical on chronographs (start, stop, reset). On dive chronographs often screw-down to guarantee water resistance.
- Perpetual calendar · Quantième Perpétuel
- High complication that displays the date including leap years correctly until the year 2100, with no manual correction at month-end, even for February. The mechanism distinguishes between months of 28, 29, 30 and 31 days via a programme wheel with a 48-month cycle. Famous: Patek 5320G, AP Royal Oak QP, Lange Saxonia Annual Calendar.
- Power reserve
- Time a fully wound mechanical watch runs without further winding. Typically 38 to 72 hours, on modern calibers like Rolex 3235 or Patek 26-330 up to 80 hours; specialist constructions like Hublot MP-05 reach over 50 days. Often displayed as an indicator ("réserve de marche") on the dial.
- Papers · Warranty card · Full set
- Original documents of a watch: warranty card (with reference number, serial number, dealer stamp), instruction manual, service receipts. Collectors call the combination of watch + box + papers a "full set"; it has a noticeably higher market value, often a 10 to 25 percent premium over the watch alone.
- Patina
- Natural traces of age on dial, indices or lume that lend a vintage watch character and history: tritium lume turns creamy ("cream"), dials shift to "tropical brown". Often desired by collectors, never to be "restored away", as patina is irreplaceable.
- Paul Newman Daytona
- Collector term for rare Daytona references (6239, 6241, 6262, 6263, 6264, 6265) with the "exotic dial", a three-colour dial with Art-Deco indices and contrasting subdials. The actor Paul Newman wore a 6239; his personal example fetched USD 17.8 million at Phillips Auctioneers in 2017. One of the most iconic vintage references in watchmaking.
- Provenance
- Seamlessly documented ownership and service history of a watch. Important for rare collector pieces; significantly increases authenticity and value. Top pieces often come with photos of the previous owner on the wrist, original invoices and a traceable service file from the manufacturer.
Q
- Quartz movement
- Electronic movement with a battery-powered quartz crystal as time base. Highly precise (±15 seconds per month) but technically simpler than a mechanical movement. The "quartz crisis" of the 1970s, triggered by Seiko Astron (1969), forced the Swiss watch industry to refocus on luxury mechanical watchmaking, a trend that continues today.
R
- Rate deviation
- Daily deviation of the watch from exact time, measured in seconds per day. Chronometer movements (COSC) must be between −4 and +6 s/day; Master Chronometer (METAS) between 0 and +5 s/day. Noticeable deviations above ±30 s/day suggest a service is due.
- Rose gold · Pink gold
- Gold alloy with elevated copper content that gives the watch a warm reddish tone. A classic at Patek Philippe (5N), Vacheron Constantin and A. Lange & Söhne. Rolex uses its in-house variant Everose with a platinum content that does not fade.
- Reference number
- Unique model identifier of a manufacturer, e.g. Rolex 116610LN (Submariner), Patek 5711/1A (Nautilus), AP 15500ST (Royal Oak). Indicates model, material (LN = bezel black, A = acier/steel) and variant. Collectors often know references by heart.
- Rotor
- Oscillating mass in an automatic movement that turns with arm movements and winds the barrel. Invented in 1931 by Rolex (perpetual system). Micro-rotors are particularly flat and are used in Patek Philippe and Piaget ultra-thin movements; at Patek often made in gold.
S
- Stainless steel 904L · Oystersteel
- Acid- and corrosion-resistant steel alloy that Rolex has used since the 1980s (Sea-Dweller) and across the entire collection from 2003. Harder to machine than industry-standard 316L but takes a finer polish and is more durable, with a finer sheen after polishing and higher resistance to salt water. Rolex has called the in-house variant Oystersteel since 2018.
- Sapphire crystal
- Scratch-resistant crystal of synthetic sapphire, only exceeded in hardness (Mohs 9) by diamond. Standard in modern luxury watches since the late 1970s. Usually anti-reflective coated on both sides for better legibility; domed on sports watches, flatter on dress watches.
- Sea-Dweller
- Deep-dive watch by Rolex, introduced in 1967 in cooperation with the diving company COMEX. Water-resistant to 1,220 m (today 3,900 m on the Deepsea), with helium escape valve for saturation dives in pressure chambers. A more robust sister model to the Submariner with a thicker case and no Cyclops until 2017.
- Serial number
- Unique identifier of an individual watch. Important for authentication, service history and insurance. On Rolex engraved between the lugs (up to about 2010 only visible without the bracelet; since 2008/2010 also on the rehaut at 6 o'clock).
- Service dial · Replacement dial
- An original dial replaced by the manufacturer during a service, usually recognisable by a different lume tone or slightly different printing. Value-reducing for collectors, as the original state is left behind; at Time Boutique always transparently documented.
- Skeletonised · Skeleton · Squelette
- Watch with a partially or fully exposed movement; the mechanics are made visible. A high craft requirement, especially for movement surfaces, bevelled edges and engraving. Famous: AP Royal Oak Skeleton, Vacheron Constantin Overseas Skeleton, Cartier Santos Skeleton.
- Speedmaster · Moonwatch
- Omega chronograph since 1957, known worldwide as the first watch on the moon (Apollo 11, 1969, worn by Buzz Aldrin). The Speedmaster Professional "Moonwatch" with hand-wound caliber 1861 / 3861 is qualified by NASA for manned space flight. A classic of the collector world with undimmed appeal.
- Submariner
- Rolex dive watch since 1953. The first series dive watch with 100 m water resistance, today 300 m. One of the most iconic sports watches of all time, worn by James Bond (Sean Connery in "Dr. No"), Steve McQueen and countless professional divers. Today references 124060 (no date) and 126610 (with date).
- Swiss Made
- A protected origin designation; since 2017 at least 60 percent of manufacturing costs and the movement must come from Switzerland (previously 50 percent). A quality seal and strong marketing advantage. Stricter labels: "Genève", "Geneva Seal" (Poinçon de Genève) and "Glashütte Original" are considered even more rigorous.
- Screw-down crown · Twinlock · Triplock
- A crown that screws into a threaded tube on the case to guarantee water resistance. Rolex distinguishes Twinlock (two gaskets, up to 100 m, e.g. Datejust) from Triplock (three gaskets, up to 1,000 m+, in Submariner, Sea-Dweller, Yacht-Master and Daytona).
T
- Tachymeter
- Scale on the bezel or rehaut to measure speeds over a fixed distance (usually 1 km or 1 mile). Widespread on chronographs, typical for Rolex Daytona and Omega Speedmaster. Works only above 60 km/h, as the scale would otherwise loop multiple times.
- Tank
- Cartier model designed in 1917 by Louis Cartier. The rectangular case is inspired by French Renault tanks from the First World War; the vertical lugs recall tank tracks. One of the most elegant watches for women and men, worn by Andy Warhol, Jackie Kennedy, Princess Diana and Michelle Obama.
- Tourbillon
- High complication to compensate the effect of gravity on the balance; the escapement rotates in a cage (usually once per minute). Invented in 1801 by Abraham-Louis Breguet for pocket watches. Today primarily an aesthetic and status feature; in wristwatches the accuracy gain is marginal, the craftsmanship enormous.
V
- Vintage watch
- In the collector world usually watches from 20 to 30 years of age and older. Value-determining: original state of the dial (patina, lume), completeness (box & papers), rarity of the reference and provenance. The line between "vintage" and "neo-vintage" (1990s–2000s) is blurring; neo-vintage has gained collector interest since 2020.
W
- Water resistance
- Protection against water ingress, measured in metres or ATM. Important: static tests do not correspond to dynamic loads. A watch with "30 m" / "3 ATM" is splash-resistant, not suitable for swimming. Real swimming needs 5 to 10 ATM, diving at least 20 ATM (200 m). Gaskets should be checked every 2 to 3 years.
- White gold
- Gold alloy with shares of palladium, nickel or silver for a cool white tone. The main material of many Patek Philippe and Vacheron Constantin dress watches as well as iconic pieces like the Day-Date in 18 kt white gold. Visually often hard to tell apart from steel, a subtle status indicator.
Y
- Yacht-Master
- Rolex model since 1992. A sporty-elegant middle ground between Submariner and Datejust, traditionally with a bidirectional rotating bezel and raised numerals. Today also available as the Yacht-Master II (regatta chronograph) and Yacht-Master 42 in RLX titanium.
More questions?
Answers to Time Boutique, buying, selling, service and more in our FAQ.Continuing
Answers about Time Boutique and our service.
The glossary explains watchmaking terms. We answer specific questions about our company, buying, selling, service, shipping and quality in our FAQ.
Term not found?
We are happy to include it in the glossary.
Write to us briefly if a watch term is missing or a definition is unclear, we will be happy to add to the glossary.