Day And Night Magazine

A
Alarm A watch feature that sounds an alarm at pre-set time or at regular intervals.

Altimeter A function that provides altitude by responding to changes in barometric pressure, commonly found in pilot watches.

Analogue An analogue watch indicates the time using hands, unlike a digital model.

Annual Calendar The automatic allowances for the different lengths of each month in the calendar module of a watch.

Anti Magnetic Anti-magnetic (non-magnetic) watches are those that are able to run with minimal deviation when exposed to a certain magnetic field.

Anti Reflection A film created by steaming the sapphire crystal covering a dial to eliminate light reflection and to improve legibility.

Aperture (or Window) The dials of some watches have apertures in which certain indications or the watch's movement are shown (e.g. the date, the hour).

Appliqué Appliqué or applied chapters are numbers or symbols cut out of a sheet of metal and stuck or riveted to a dial.

Arabic Numerals 1, 2, 3, etc., allow greater scope for fantasy than their Roman counterparts. The majority of fine watch companies use both Arabic and Roman numerals without distinction.

Atmosphere (ATM) Unit of pressure used in watch making to indicate water-resistance. One Atmosphere Pressure (1 ATM) approximately corresponds to a water depth of 10 metres.

Automatic Winding A watch whose mainspring is wound by the movements of the wearer's arm. (Also known as self winding).

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B
Baguette Ladies style watch with a thin, elongated face; usually rectangular in shape but may be oval.

Balance Wheel The regulating organ of the watch, vibrating on a spiral hairspring. Lengthening or shortening the balance-spring makes the balance-wheel go faster or slower to advance or retard the watch. This is the wheel that is driven by the main spring and that is controlled by the escapement.

Barrel Used in mechanical watches (and clocks), a barrel is a cylindrical metal box closed by a cover, with a ring of gear teeth around it, containing a spiral spring called the mainspring, which provides power to run the timepiece.

Battery Device that converts chemical energy into electricity. Most watch batteries are the silver oxide type delivering 1.5 volts.

Bezel The ring surrounding the watch dial and sapphire crystal.

Bridge A watch bridge is a watch part attached to the main plate to help form the frame of a watch movement.

Brushed Steel Brushed Steel (or metal) is steel (or metal) that has been abraded ("brushed"), usually with fine grit sandpaper. The brushing gives the metal a distinctive look, as it retains some of its metallic lustre and is given a pattern of very fine lines.

Buckle Usually matching the case, it attaches the two parts of the leather strap around the wrist.

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C
Cabochon The decorative stone set in the watch crown.

Calendar A watch feature that shows the date and sometimes, the day of the week and the month. It can be displayed through a cut-out window in the dial, as a sub-dial with small hands indicating the day/date feature or by digital readout.

Calibre A term that indicates a kind of watch movement. Calibres come in many variations.

Carrousel This device was invented by a Danish watchmaker and is similar to a tourbillon.

Case The main body of the watch containing the watch movement or main components.

Case Back The protective cover at the back of the watch case which can be removed to allow access to the internal watch movements for maintenance.

Chronograph A watch with 2 independent time systems.

Chronometer A precision watch that is set in varying conditions meeting the accuracy standards set by the official watch institute in Switzerland. Most major watch companies provide this certificate to a buyer at the time of purchase.

Clasp The attachment used to connect the two ends of the watch bracelet or strap around the wrist.

Complicated Watches Any function other than the indication of hours, minutes and seconds.

COSC The Control Officiel Suisse de Chronometers, an independent regulatory council in Switzerland that tests and certifies watch movements for chronometer status.

Cotes de Genève Decoration on a dial comprising an even pattern of parallel stripes.

Countdown Timer A function that lets the wearer keep track of how much of a preset period of time has elapsed

Crown Nodule extending from the case that is used to set the time, date or any other function. Most pull out to set the time.

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D
Deployment Buckle A three-folding enclosure which secures the two ends of the bracelet and allows enough room for placing the watch on the wrist when fully deployed. When closed the buckle covers the two-piece folding mechanism.

Dial Face plate set into a watch case, bearing various markings to show the hours, minutes, seconds or other functions.

Digital Any watch that shows the time in numbers instead of hands on the dial. The numbers appear in LCD (Liquid Crystal Diode) which shows a continuous reading or LED (Light Emitting Diode) which shows time at the push of a button.

Divers Watch Diver's watches are designed and manufactured especially for divers whose lives depend on the reliability of their watch in the water. Diver's watches should meet ISO (International Standardization Organization) regulations.

Dual Timer A watch that measures current local time as well as one other time zone.

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E
Enamel A glassy substance usually opaque applied by fusion to the surface of metal or glass for ornamental or protective purposes.

Escapement Set of parts which converts the rotary motion of the train into to-and-fro motion.

ETA One of the leading manufacturers of watch movements based in Switzerland, used by many major Swiss brands.

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F
Flange The external or internal rib or rim in a watch case for support or attachment .

Fly-Back Chronograph An additional centre seconds hand in a chronograph watch which can remain super-imposed on the other one as it moves. It can be stopped independently and then made to "fly back" so as to catch up with the other hand. It can be stopped and reset to zero together with the other hand.

Frequency The number of vibrations a second in hertz (Hz).

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G
Gear Train The interconnected system of gears and pinions which transmit power from the mainspring to the escapement.

GMT Greenwich Mean Time (GMT) as set to the international clock in Greenwich, England.

Guilloche A type of engraving on a dial in which thin, often hand machined lines are interwoven in a pattern.

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H
Hallmark An engraved mark on the back of gold watches which prove that the material used is genuine gold.

Hands A watch usually has three hands to show the hours, minutes and seconds.

Horn The part of the watch case to which the strap is attached.

Horology The science of time measurement including the art of designing and constructing timepieces.

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I
Incabloc A popular device for protecting the delicate components of a mechanical watch mechanism from impact by acting as a type of shock absorber. The name Incabloc is a trade mark name.

Index An hour indicator on an analog watch dial used instead of numerals.

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J
Jewel Bearing, end stone or pallet used for reducing friction in a movement.

Jumping Hour Refers to a mechanical or quartz watch with an unconventional layout for the hour hand. Whilst the minute and second hands are displayed as normal on the watch dial, the hour hand is displayed in a small dedicated cut-out on the dial, often positioned centrally at the top. As the minute hand reaches each hour, the hour hand jumps to the next hour giving rise to the name.

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L
Lug A thin metal rod fixed between the horns, for attaching the wrist band.

Luminous Self illuminating paint used on hands and markers.

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M
Main Spring The 'engine' of a mechanical watch-a large flat spring made from a piece of metal or composite.

Manufacture A watch company that uses a movement in at least one of its models that it has manufactured itself on its own premises.

Marine Chronometer Highly accurate mechanical timekeeper used for determining the longitude on board a ship.

Mechanical Movement A movement based on a mainspring which is wound by hand. When wound it slowly unwinds the spring in an even motion.

Micro Second One millionth of a second.

Minute repeater A striking mechanism with hammers and gongs for acoustically signalling the hours, quarter hours, and minutes elapsed since noon or midnight.

Moon Phase An indicator that keeps track of the phases of the moon.

Movement The assembly of mechanisms and other internal elements of any timepiece.

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N
Nanosecond One billionth of a second.

Nivarox Nivarox is a type of antimagnetic steel alloy that is used in balance springs.

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O
Oscillation Also referred to as ‘Vibration’. The travel of the balance wheel from one extreme to the other and back again.

Oval Some types of watches have an oval shape.

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P
Perpetual Calendar A type of calendar that automatically adjusts for months of different lengths and indicates February 29 in each leap year.

Pinion A watch part generally with 6 to 14 teeth.

Power Reserve The period a watch will continue to function before the mainspring must be wound.

Push Piece / Push Button Button that is pressed to work a mechanism.

PVD Physical Vapour Deposition. Method of coating thin watch cases by integrating titanium particles and then depositing gold for colour.

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Q
Quartz Movement A quartz movement uses a stable vibration frequency of a quartz crystal subjected to electronic tension with the help of outside energy.

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R
Rattrapante A term used to describe a double or split second feature of a chronograph watch consisting of two overlapping second hands, one of which is for the normal second function and the other a fly-back hand.

Repeater A watch that strikes the time on request is known as a repeater. There are one-minute, five-minute, quarter-hour and hour repeaters.

Retrograde Hands The pointer hand on the dial of a watch, whether the main dial or a sub-dial (or register), which returns to the zero position at the end of a fixed period.

Roman Numerals I, II, III etc. Some fine watches use Roman numerals on the dial face.

Rotating Bezel A bezel that can be turned, typically in an anti-clockwise direction. Whilst the reasons for a rotating bezel can vary, they are often associated with time keeping for watches with a diving theme.

Rotor The mass or weight of an automatic watch movement which rotates to wind the mainspring, usually in one direction, though reverser gears.

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S
Sapphire Crystal A thin sheet of glass or a transparent synthetic material to protect a watch dial.

Screw down locking Crown A crown that aids water resistance by sealing the crown against the case.

Shock-Resistance A shock-resistant watch is one which can withstand normal wear and tear even during strenuous sports activities.

Skeleton Watch Watch in which the case and various parts of the movement are of a transparent material, enabling the main parts of the watch to be seen.

Sonnerie A type of minute repeater that automatically sounds the time.

Split-Seconds Chronograph A second chronograph that runs concurrently with the first but can be stopped independently to record intermediate time.

Striking Mechanism An acoustic device that automatically or on demand indicates the hour and possibly quarter-hour and minutes or sounds at a pre-set hour.

Subdial A small dial used for any of several purposes such as keeping track of elapsed minutes or hours on a chronograph or indicating the date.

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T
Tachymeter A watch function that measures the speed at which the wearer travelled by means of a numeric scale on the watch bezel of a chronograph.

Tonneau Watch A watch with a barrel-shaped case with two convex sides.

Tourbillon A device in some mechanical watches that eliminates timekeeping errors caused by slight variations due to shifts in gravity when a watch changes position during use.

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U
Unidirectional bezel This is a type of rotating bezel that only moves in one direction.

Universal Time Co-ordinated (UTC) Is the time standard by which the world regulates clocks and time. Computer servers, online services and other entities that rely on having a universally accepted time use UTC for that purpose. Coordinated Universal Time is a time standard based on International Atomic Time (TAI) with leap seconds added at irregular intervals to compensate for the Earth’s slowing rotation.

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V
Vibrations In most mechanical watches, the movement balance makes 18,000 vibrations per hour.

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W
Water Resistance A watch bearing the inscription ''water-resistant'' on its case back can handle light moisture, such as a rainstorm or sink splashes, but should not be worn swimming or diving. If the watch can be submerged in water, it must state at what depth it maintains water-resistance, for example 50 meters (165 feet) or more on most sport watches.

Winding Mechanism The mechanism which tightens the mainspring in a watch.

World Timer A watch with a dial that indicates up to 24 time zones around the world, usually found on the outer edge of the face or sometimes on the bezel.

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X
X-rays X-rays do not damage watches, including mechanical ones.

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Y
Yacht Timer A countdown timer that sounds warning signals during the countdown for a boat race.

Year Some watches are able to show the year on the dial.

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Z
Zalium Zalium is an alloy of aluminium and zirconium sometimes used in watchmaking.

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Watchmaking Terms

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