Horology Society Top100 Watch Sites
To use some of the services or features made available to you on our site, you will need to register. We may change registration requirements from time to time. When you register, you are required to provide information about yourself that is true, accurate, current and complete in all respects. Should any of your registration information change, please notify us immediately at the following e-mail address This e-mail address is being protected from spambots

Credit Cards Accepted Here
watchintime on Facebook



A/h; vibrations of the balance per hour. Two vibrations make the well-known tick-tock sound of the mechanical watch, known as one oscillation.
Alarm; Watch fitted with a ringing mechanism that is automatically released at the required time.
Amplitude (Vibration); Angle of oscillation for the balance.
Antimagnetic watches; Watches not, or hardly, affected by magnetic fields. For the balance springs of the balance non-magnetic nickel alloys are used.
Automat, Automatic; Synonym for a watch Automatic with automatic winding. The movement of your wrist makes the rotor (oscillating weight) turn, thereby winding the mainspring of the watch movement.


Balance Spring

Balance spring;
The hairspring and the balance form the oscillating system. The balance spring of a watch consists of a thin and flat wire made of Nivarox.

Balance Wheel Balance wheel; Part of the escapement of a mechanical watch. Oscillating device which divides the time into equal sections.

Barrel Barrel; The barrel contains the wound-up mainspring, hooked to it at its outer end and which stores the energy, assuring a power reserve of 36 to 45 hours to the watch. The mainspring is wound up manually by means of the crown (handwinding watch) or through the movement of the oscillating weight (Rotor) in an automatic watch.

Bridge; brass plate fixed on the main plate by two or more pins and screws. Between the bridge and the plate the wheels and staffs are turning.

Bezel; Top ring for the crystal and/or decorative ring on the upper side of the watch case.


Calibre; Description for a watch movement according to construction, size and factory origin.
Cal.; Abbreviation for Calibre. Synonym for a watch movement defined by construction and size.
Carat; 1 Carat = 1/24 fine gold of a gold alloy. An 18 carat gold alloy contains 18/24 fine gold = 75% fine gold content.
Chronograph; Wrist or pocket watch incorporating an additional stop mechanism (start, stop and back to zero functions).
Chronometer; a watch of extremely high precision and accuracy, tested in several positions and under different temperatures and which has obtained an official rating certificate.
Complication; Additional functions to a watch movement, e.g. chronograph, second time zone, alarm, calendars etc.
Crown; Button to wind up and set the watch to time.


Daily Rate; Term used to denote the difference of time adjustment after 24 hours. There can be differences of up to several seconds per day according to quality and place or quality and wearing conditions.
Date Display; Display of date on the dial of a watch. In mechanical watches discs or bars are used for this purpose, which are connected to the movement by means of transmission wheels.
Differences; In accordance with the type of movement used, the daily rate may vary between -5 to +20 seconds. These tolerances are within the limits laid down by many watch manufacturers.
Divers Watch; Specially constructed wrist watch for deep sea diving. Divers watches are fitted with screw-in crowns, and they are guaranteed to withstand underwater pressures of 20 ATM (200 m).


Ebauche, Movement Blank; Incomplete watch movement in principle without mainspring and balance. The movement blanks are assembled, refined and completed with the missing parts.
Escapement Wheel; The escapement wheel and the lever build the escapement. It is the last train wheel.
Escapement; Mechanism built in between the gear train and balance wheel. The escapement transfers the power from the gear train in regular and even time sequences to the balance, the oscillating system. Escapement


Fine Time Adjustment; Regulating lever to adjust the daily time accurately. The majority of watches are fitted with a regulating lever for particularly precise time adjustment.
Frequency; Number of vibrations per hour.


Gasket; The majority of water resistant watches are equipped with gaskets in the case back, the crystal and the crown.
Gear-Train; The system of wheels and pinions which, from the barrel B, transmits the driving power to the escape wheel E, Z1 centre-wheel, Z3 third wheel, Z5 fourth wheel. E escape wheel. All these wheels are riveted to their respective pinions, Z2, Z4, Z6. Gear Train
Glucydur; first rate metal alloy used for balances of top quality.
Gold Plating; Electro deposited layer of gold, the thickness of which is given in microns.


Handwinder, Hand winding; A watch whose mainspring is wound up daily by means of the winding crown.
Hertz Heinrich; German physicist (1857-1894). The word Hertz is now used as physical measurement for the frequencies (numbers of vibrations), indicated as oscillation per second.
High Frequency Movement; Watches which make a minimum of 28'800 vibrations.


Incabloc; Trade mark of a Swiss shockabsorber (see Shock-absorber).
Instantaneous Date; Instantaneous date means that the date changes instantaneously at midnight.


Jewel; English term for Ruby (see Ruby).
Jewelled Lever Escapement; Lever with pallet of synthetic ruby.

KKnurling Tool

Knurling Tool; This tool is used in the production of bezels.


Made in Switzerland; Produced and assembled in Switzerland.


Mainspring; Flat coiled spring that powers all mechanical watches.
Marine Chronometer; Highly accurate mechanical or electronic timekeeper enclosed in a box (hence the term box chronometer), used for determining the longitude on board ship. Marine chronometers with mechanical movements are mounted on gimbals so that they remain in the horizontal position is necessary for their precision.

Mechanical Watches; Watch that stores the running power by means of a mainspring. The mainspring is either wound up manually in a handwinding watch or in an automatic watch by the swinging weight (Rotor) Mechanical Watches through the movement of the arm.

Micron; 1/1000 mm or 0.00l millimetre used for instance to measure the thickness of gold plating.
Mineral Crystal; Mineral, mostly flat watch crystals. Mineral crystals are hardened after polishing and therefore less sensitive to scratches and plexi crystals.
Moonphase Display; Display of the 29 1/2 days' cycle of the moon by means of a dark blue disc turning below the dial by the gear-train.


Nivarox; Alloy for the manufacture of balance springs.


Official Certificate; (see Chronometer)



Pallet; Part of the lever escapement, shaped like a ship's anchor (see Escapement).

Plate (Bottom Plate); The plate supports the bridges and the various parts of the movement. The movement plate and the bridges build the frame of the movement.
Plexi Crystal; Watch crystal made of acryl crystal. This material can be processed and polished easily. The advantage for the owner of the watch is the comparatively high resistance to shocks.
Pointer Calendar; English expression for a calendar watch with a hand that points to the date as opposed to a calendar watch where the date appears in a window.
Power Reserve; Running time for a watch fully wound up until it stops.
Push Pin; Small metallic spring pin fixed between the horns of the case to hold the watch strap.
PVD; An abbreviation which stands for Physical Vapour Deposition. The PVD technology used for watches and bracelets is one of the most up-to-date and non-polluting coating systems. Its quality can be compared to 10 micron gold plating. The PVD finish is highly scratchproof and long lasting. The authentic gilt colour tone is obtained by applying a 23 carat gold layer.


Quartz Watches; Watches with analogue or digital display, whose movement is powered by a quartz. The quartz analogue watch: The division of the time functions by means of quartz, whose vibrations are generated by a battery. The analogue time display is shown by electrically driven hands. In digital watches the display is, in most cases, by liquid crystal numerals. Quartz Watches

Quick Change Corrector (Date); Mechanism for the direct setting of the date, to avoid turning the hands over 24 hours.


Regulating; With fine regulating the watchmaker adjusts a watch to run as accurately as possible (see Fine Time Adjustment).
Repeater; Watch that strikes the hours by means of a mechanism operated by a push-piece or bolt. There are various types of repeaters. Quarter-repeater: sounding a low note for the hours and a "ding-dong" for each of the quarters; Five-minute repeater: striking the hours, quarters and five-minute periods after the quarter; Minute-repeater: striking the hours, quarters and minutes; Grande sonnerie (grand strike): striking the hours and quarters automatically and repeating when a push-piece is pressed down; Chiming repeater: in which the quarters are struck on three or four gongs of different pitch.
Rotating Top Ring; Rotating bezel on the top ring of a watch case, serving in most instances to record additional data.
Rose Gold; Alloy of gold, copper and silver. The rose gold tone is due to the copper content.
Rotor; (see Swinging or Oscillating Weight).
Ruby; Synthetically produced precious stone, used in the watch movement as pallet stones and bearings (jewel holes) to reduce friction and wear.


Sapphire Crystal; Watch crystal made of artificial sapphire. A sapphire crystal is highly scratch resistant due to its extreme hardness.
Selfwinding; (see Automatic).
Screw Back; Case back with thread so that is can be screwed on to the watch case.
Screw-in Crown; Special crown which is screwed in for better security and used mainly for diver's and sports watches.
Setting Mechanism; By pulling out the crown the time and date can be set. The core of this complex mechanism is the cannon pinion, fitted with a special kind of coupling-clutch. This enables the watch to be set independently from the gear-train.

Setting Mechanism

Shock-Absorber; Principle: the endstone a is subject to the action of a spring b. If an axial shock occurs, the endstone can lift slightly until the shoulder c strikes a fixed part of the setting. To damp lateral shocks, the jewel hole is fitted in a setting comprising an inclined plane d which provides for a slight lateral shift limited by the collet-arbor or by the roller-arbor e which strikes a fixed part of the framework.

Small Second; Second display not from the centre, but by a hand in a subsidiary small dial. This type of second implies a different construction of the movement.

Stainless Steel; Steel which does not get rusty and is not affected by corrosion. It is extremely resilient.
Swinging Or Oscillating Weight (Rotor); The natural movement of the arm makes the oscillating weight swing round, thus winding up the mainspring of the automatic watch.


Tachometer (Tachymeter); The tachometer division on the dial of a chronograph serves to measure the speed, e.g. of a car on a measured course of 1 km or 1 mile. At the moment the car passed the starting point of the course, the chronograph is set and stopped at the final point of the course. The position of the stopped hand on the tachometer scale corresponds to the speed in km (miles) per hour. The speed over the whole test run must be the same.
Tritium; Isotop of hydrogen, slightly radio-active, is used to activate the luminous dots on the dial. The emitted radiation is so low that there is no health risk.


Vibrations; (see Amplitude)


Waterproof; English term for water resistant watches.
Water Resistance; Watch case, crown, buttons (push-pieces) and crystal are water resistant and dustproof up to the underwater pressure or depth mentioned by the manufacturer. The water resistance should be checked yearly.
Winding System; Shaft on which the crown is fixed at the outer end. The winding system is the connection to the watch movement.