⌚Glossary | Chrono Hunter |The Best Way To Buy or Sell a Watch

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Glossary

Not sure what all the specialist words and terms mean. Try our glossary out and if you can’t find what you are looking for do send us an email.
a
  • Automatic

    A mechanical watch that is powered by the motion of the wearer. It needs no winding or batteries.

b
  • Balance spring

    Sometimes known as a hairspring, this is attached to the balance wheel to regulate its rate of oscillation.

  • Balance wheel

    Regulates the time and moves the watch’s hands by oscillating at a constant rate to power the watch’s gears.

  • Barrel

    A cylinder with geared teeth that houses the mainspring.

  • Bezel

    The ring that surrounds the face of the watch. Usually made of metal or ceramic, they can be purely decorative or functional. Some have scales that can be used as tachymeters and bezels on dive watches can be rotated to indicate time elapsed under water.

  • Bridge

    Part of a mechanical watch that is mounted to the mainplate to make a frame to house the inner workings.

c
  • Caliber

    Another word for “movement”.

  • Case back

    The under side of the watch face. Some are made of crystal to display the movements inside.

  • Chronograph

    A watch that features a stopwatch function.

  • Chronometer

    A watch certified by the Contrôle Officiel Suisse des Chronomètres (COSC). Mechanical watches must be accurate to within +4 and -6 seconds per day and quartz watches by ±0.07 per day.

  • Complication

    Any function of a watch other than simple time indication.

  • Crown

    The knob on the side of the watch case that is used to wind the watch and/or set the time and date.

  • Crystal

    The “glass” that protects the face of the watch. It is usually made from acrylic, glass or synthetic sapphire.

d
  • Deployment clasp

    A strap closure that folds in itself to be held in place with a clasp. They can extend the life of leather straps as they avoid the damage sometimes caused by buckles.

  • Dial

    The face of the watch featuring numeral markings and manufacturer branding.

  • Dive watch

    A watch specifically designed for divers. Most are water-resistant to 200 metres, have luminous hands and moving bezels to signal the amount of time the diver has spent underwater.

e
  • Escapement

    The part of the watch that moves the second hand and is responsible for its ticking.

f
  • Flyback chronograph

    A stopwatch that can record multiple times.

  • Frequency

    The speed at which a watch ticks, governed by the oscillations of the balance wheel.

g
  • Gasket

    The rubber or plastic ring used to seal gaps when closing the case back. Prevents the entry of water or dust.

  • Gear train

    The system that powers the escapement from the mainspring.

  • GMT

    Stands for Greenwich Mean Time but describes any watch that has an extra hour hand so the time in two zones can be indicated at once.

h
  • Hacking seconds

    A function that stops the seconds hand when the crown is pulled out allowing synchronisation with other timepieces.

  • Horologist

    One interested in the science, or art of time. Also a maker of clocks or watches.

  • Horology

    The science, or some may say art, of measuring time.

i
  • Indices

    Hour markers applied to the face of the watch.

j
  • Jewels

    Synthetic rubies or sapphires used to reduce friction in the movement of a watch.

l
  • Lugs

    The pieces of metal at the top and bottom of the case that are used to attach the strap or bracelet.

  • Luminescence

    The glow given to numerals and hands, typically on dive watches. Most watch manufacturers use strontium aluminate which is not radioactive.

m
  • Magnetism

    The loss of accuracy caused when the balance spring becomes magnetised. This is easily remedied by a watchmaker, but some watches are anti-magnetic, with the movement protected by soft iron cages. Balance springs can also be made of silicon, which cannot become magnetised.

  • Mainplate

    The base of a movement on which all the mechanical parts are mounted.

  • Mainspring

    The spring that is tightened when the watch is wound. The unwinding of the spring powers the watch.

  • Manufacture d’Horologie

    A company that develops its own parts and movements rather than buying them from suppliers.

  • Movement

    The mechanism that powers all the functions of the watch. Can be automatic, hand-wound or battery powered (quartz).

p
  • Power reserve

    The length of time a fully-wound automatic watch will continue to run if it is not worn or moved.

q
  • Quartz

    A battery-powered watch.

r
  • Repeater

    A watch that chimes to tell the time in response to the push of a button.

s
  • Skeleton

    A watch with a dial that has gaps to display the movement from the front.

  • Small seconds

    A second, smaller dial on the watch’s face that displays the seconds.

t
  • Tourbillon

    An escapement housed in a rotating cage to counter the effects of gravity on the movement. They usually feature on very high-end watches and are displayed through a hole in the watch’s face.

w
  • Winder

    A rotating box that keeps an automatic watch fully wound when it is not being worn.