A

Alarm

A device that generates a signal at a specified time. Alarms in wristwatches include audible signals (beeps, tunes, etc.), vibrations (buzzers), and shocks.

Altimeter

A device that indicates the distance above or below mean sea level. Altimeters used in watches are usually based on sensors which respond to changes in atmospheric pressure.

Ana-Digi

A wristwatch containing both digital and analog functions.

Analog

A wristwatch that uses moving hands to indicate the time.

Annual Calendar

Calendar function that correctly deals with the irregular number of days per month. Annual calendars are not capable of dealing with leap years. This requires a perpetual calendar function.

Atomic Clock

Term used to describe method of timekeeping based on counting radioactive emissions from a specific amount of Cesium. Atomic clocks, due to their very high accuracy, are used as time standards for most scientific applications involving timekeeping. Atomic clocks are on board the satellites which generate the timing signals used in the Global Positioning System (GPS).

Atomic Time

A term used to describe wristwatches which receive radio signals transmitted by governmental time standard agencies to maintain accurate time in the watch. In the United States, these signals are transmitted from radio towers in Boulder, Colorado and Hilo, Hawaii.

Automatic Winding

Method of winding the main spring of a mechanical watch depending on movement of the wearer’s arm. This is usually accomplished by an eccentric weight mounted on a rotor and connected by gears to the barrel, which contains the mainspring. Simple automatic winding mechanisms operate in only one rotational direction. More complicated mechanisms work in both directions. This feature is also referred to as “self winding”. Other brands use the term “perpetual” for their automatic winding mechanisms.

B

Barometer

A device that indicates atmospheric pressure. Wristwatch barometers include electronic pressure sensors, and in some instances, air bubbles inside columns of liquid.

Bezel

A term used to describe the part of a pocket watch case which closes on the dial side of the pocket watch and holds the glass of the watch face. In wristwatches, the term bezel is used to describe the watch case which holds the glass, into which the case back is snapped or screwed.

Bracelet

An attachment to a watch head that holds the watch on the arm. The term bracelet is used for all such attachments except those made of leather, which are traditionally referred to as straps.

Buckle

The device that connects two sides of a bracelet or strap.

Butterfly Clasp

A buckle that expands to allow the watch to fit over the wearer’s wrist, and then collapses to form a snug fit. A butterfly clasp used on a bracelet allows the bracelet to appear to be continuous since the collapsing of the butterfly clasp hides the clasp.

C

C.O.S.C.

Abbreviation: Contrôle Officiel Suisse des Chronomètres aka Swiss Official Chronometer Testing Institute. The Swiss organization responsible for testing movements for timekeeping accuracy. Movements which pass these tests are issued an official certificate, which is usually passed on to the purchaser of the watch containing the certified movement.

Calendar

Function to indicate day, date, month and/or year.

Caliber

Term used to describe type of movement. For example, Timex Caliber 921 is a chronograph movement and Timex Caliber 2892 is a mechanical movement.

Case

The housing for the movement, dial and crystal.

Chronograph

Stopwatch function. Literally, a device that writes (graph) the time (chronos). The original chronograph devices indicated the beginning and end of a time interval by writing a dot on the dial. Today’s chronographs use hands or digital numerals to indicate, measure and record time intervals. Typical chronograph resolutions are ¹/₄ second, ¹/₅ second, ¹/₁₀ second and ¹/₂₀ second.

Chronometer

An accurate timekeeping device. The accuracy of which has been certified by bodies such as C.O.S.C. Mechanical chronometers are required to maintain accuracy within the daily limits of +6/-4 seconds. Quartz chronometers must maintain daily accuracy limits of +/- 0.02 seconds.

Clasp

A device used to connect two sides of an attachment.

Compass

A device that indicates the location of the earth’s magnetic pole.

Crown

The “knob” used to set the time and/or date functions.

Crystal

The clear lens that covers the “face” of the watch, often made of plastic, glass, mineral glass (a harder glass composite that is resistant to scratching and breaking), or sapphire crystal.

D

Dial

The decorative “face” of the watch.

Digital

Telling time with numbers. Typical digital watches use the HH:MM (Hours:Minutes) or HH:MM:SS (Hours:Minutes:Seconds) formats.

E

Escapement

Part of mechanism that alternately blocks and unblocks the gear train of a mechanical watch. The escapement includes the hairspring, balance wheel, and pallet lever. The accuracy of a mechanical watch is largely determined by the design of the escapement.

Eye

The portion of a watch dial swept by a small hand which is not mounted in the center of the dial. Typically the eyes are used in chronograph watches where there is a need to show elapsed intervals involving hours, minutes, seconds, and fractions of seconds. However, eyes are also used for features such as a small second hand, calendars, and power reserve indicators.

F

Flyback Chronograph

A type of chronograph developed for aviators which allows for immediate restart of chronograph function upon the push of a button. In most flyback chronographs the elapsed seconds interval is indicated by a center mounted hand (sweep second) which “flies back” to zero (12-o’clock) when the pusher is activated and then immediately restarts measuring elapsed time. This feature was useful to pilots when they needed to fly a “box pattern” waiting for permission to land and wanted to fly an equal amount of time in each leg of the box pattern. Of particular interest in most high quality flyback chronographs is the sweep hand’s return-to-zero direction: counter-clockwise when the sweep hand is in the range 1-30 seconds; clockwise after the sweep passes 30. This ensures the fastest “return-to-zero”.

Fob Watch

A watch designed to be worn by clipping or pinning to clothing with a chain. These watches were historically very popular in Eastern countries (China and Japan in particular). The most common type of fob watch in the West is the “Nurse’s Watch” – a fob watch with a red sweep second hand used by nurses when taking the pulse of a patient.

G

Gear Train

The mechanism that drives the hands of an analog watch. In a mechanical watch the gear train converts the energy stored in the mainspring into rotation of the hands. In a Quartz Analog watch, the gear train is activated by the motor and moves the hands.

GMT

Abbreviation: Greenwich Mean Time
Since the Englishman Benjamin Harrison was the first person to make a chronometer, the “zero” line of longitude runs through the Royal Observatory at Greenwich, England. In maritime history, accurate measurement of time (see chronometer) was the best method to determine longitude when sailing away from the sight of land. England’s ability to determine this before any other country played an important role in the creation of the British Empire.
In the past, people determined time by the sun, noon in a particular location was the time when the sun was directly overhead. Obviously, this resulted in many different “noons” around the globe. This system worked well until the development of the railroad – the first vehicles which could travel fast enough to make the time differences inherent in “solar time” a problem. The adoption of a “standard time” was a logical development.
Greenwich Mean Time simply refers to the time kept at Greenwich. All of the other Time Zones in the world are measured against this time. For instance, the time in Middlebury, Connecticut – site of Timex Group Watch Hill Headquarters – is five hours behind the time in Greenwich and is therfore referred to as GMT-5.
 
Universal Time
Universal time is the modern (1928) version of Greenwich Mean Time.

GPS

Abbreviation: Global Positioning System
A United States military system comprised of a number of low earth orbit satellites, each carrying a calibrated atomic clock, which transmit radio signals identifying their orbital data and the precise time. A ground-based receiver can convert the data from a minimum of three satellites into an accurate (+/- 3 meters) location.

Guilloche

A French term used to describe a manually operated turning engine which can cut elaborately decorated patterns. The engine is controlled by a set of cams referred to as the “rose”. Many high-end watches have dials which have been decorated using guillochage.

H

Hair Spring

Tiny spring used in the escapement of a mechanical movement to regulate the release of energy in the main spring to the gear train. The hair spring and balance wheel are the mechanical equivalent of a pendulum and provide the time base for a mechanical movement.

HRM

Abbreviation: Heart Rate Monitor
A device to measure a person’s pulse rate (number of heart muscle contractions per minute). Modern heart rate monitor watches consist of a chest strap which contains a sensor system to detect the electrical activity of the heart and a radio to transmit this data to a wristwatch. Timex’s family of HRMs uses digitally coded radio transmissions to ensure accurate readings at all times.

I

Indicia

Mark placed on dial to indicate increment of time.

Indiglo®

A patented lighting system that uniformly illuminates the entire watch dial for ease in telling time in low light conditions. Timex’s Indiglo lighting system is based on electroluminescence – a phenomenon associated with certain materials that convert electrical excitation into visible light.

J

Jewel

The term used for the synthetic rubies in mechanical watch movements that are placed under wheels and pinions to reduce friction.

K

Kinetic

Seiko’s term for an automatic winding system that powers a miniature generator and supplies electrical energy to charge a capacitor or rechargeable battery powering a Quartz Analog movement.

L

LCD

Abbreviation: Liquid Crystal Display
Organic materials which can polarize light are used in digital watches as the display. An electric signal is provided to electrodes printed on the display, which causes the organic material (the liquid crystal) to polarize light. The numbers you see on a digital display are actually areas where the light striking the display was polarized and was not reflected back to the surface.

LED

abbreviation: Light Emitting Diode
A solid state device which converts electrical energy into light. The first LEDs could only generate red light. Modern LEDs emit blue, red, amber, and even white light.

Linear Indicator

Most motion in a watch movement is circular, the wheels go “round and round”. Converting this circular motion into “straight line” motion in the tiny space available in a watch movement is a great challenge. Very few watches exist with hands which move in a straight line (linear) fashion.

Luminescence

Certain materials exist which can “glow” a long time after having been exposed to light. Luminescence is a property of materials related to the existence of meta-stable electronic orbitals. Materials which are luminescent absorb light energy, moving electrons to meta-stable orbitals, and later emit light energy as the electrons decay back to their stable energy levels.

M

Main Spring

Large coiled spring that is the main power source of mechanical watches; the main spring drives the mechanism as it uncoils.

Mechanical Watch

A timekeeping device powered by a main spring and regulated by a hair spring/escapement.

Module

Insides of a digital watch containing battery, microprocessor, display and sometimes a sensor. The module is the term we use instead of movement for the “insides” of a digital watch.

Moon Phase

The moon rotates about the earth in a period of approximately 29.5 days. At any position on the earth the appearance (phase) of the moon will vary from “full” to “new moon” (not visible) over this period. Watches which display the appearance of the moon, usually in an “eye”, are quite popular.

Movement

The mechanism that turns the hands of an analog watch.

P

Pedometer

A device which counts steps, usually based on a miniature pendulum or an electronic accelerometer.

Pendulum

A weight suspended from a fixed point that allows free-swinging motions to occur. A pendulum will swing back and forth at a roughly regular rate, which can be used in a clock to measure time.

Perpetual Calendar

A calendar function that correctly deals with the irregular number of days per month and understands Leap Years. There are special rules governing Leap Years which are based on the irregularity of the earth’s motion around the sun. For instance, the year 2000 was not a Leap Year, even though it was evenly divisible by four.

Photovoltaic

From the Greek (photo = light, volta = spark). A material that generates an electric voltage when exposed to light. See “Solar Power”.

Pocket Watch

A watch designed to be worn in a pocket.

Pulsometer

The dial of a watch with a second hand can be marked to show pulse rate on the assumption that a fixed number, usually ten, of pulse beats are observed and then the position of the second hand &rlquo;tells” the pulse rate. For instance, a pulsometer dial would show the number 40 at 3-o’clock.

Q

Quartz Analog

A movement that drives hands and using a quartz crystal tuning fork instead of a hair spring as its timebase.

R

Retrograde

A term used to describe hands that can move both forwards (clockwise) and backwards (counter-clockwise).

Rotor

The part of the motor of a Quartz Analog movement, which rotates under the influence of the induced magnetic field in the stator.

S

Sapphire Crystal

Sapphire is a hard, transparent, scratch resistant material used as the crystal of high-end watches. Some mechanical watches also use sapphire as the back of the watch case, in order to expose the watch movement.

Screw Down Crown

A crown designed to provide greater water resistance through screw threads and a gasket. In normal use this type of crown is firmly screwed into the bezel. The crown must be unscrewed before it can be used to set the time.

Sensor

A device that “senses” some physical parameter. Sensors used in watches include devices to indicate temperature, pressure, humidity, and ultra-violet radiation.

Shock Resistance

The ability of a wristwatch to undergo physical shock and continue to function accurately. The unit of shock is the “g”, representing the force of the earth’s gravity. Typical Timex watches are shock resistant to forces exceeding 3,000 g.

Solar Power

Certain materials can convert sunlight into electrical energy. These materials are called “photovoltaic”. Watches that incorporate photovoltaic materials as energy sources are referred to as “solar powered” watches.

Speed and Distance

Runners are interested in how fast they are running (speed) and how far they have run (distance). Timex was the first company to introduce a “speed and distance” product for runners, combining data from a Global Positioning System device with timing data from a Timex Ironman runner’s watch.

Spring Bar

A clever method to fasten a watch attachment (strap or band) to the lugs of a watch case is to use a cylindrical mechanism that contains a spring which pushes against pins at each end of the cylinder. This mechanism is called a spring bar, enabling the attachment to be fastened to the watch by first depressing one of the spring-loaded pins and then allowing the pin to expand into a hole in the lug; the process is repeated for the other pin.

Stator

The part of a quartz analog stepping motor, usually made of a very soft iron compound, which is rigidly fastened to the movement frame so that it cannot move (stator comes from static). The stator is magnetized under control of the quartz analog integrated circuit, and the magnetic field in the stator interacts with the permanent magnetic field of the rotor, causing the rotor to turn. A quartz analog stepping motor is designed to change the polarity (direction of the magnetic field) of the stator to first start the rotor turning and then stop it after it has moved, usually 180 degrees. This “start then stop” sequence is why the second hand of a Quartz analog movement seems to jump one second at a time.

Strap

A watch attachment made of fabric, rubber, plastic or leather.

Sub Second Hand

A small second hand that is not center-mounted. This type of second hand is often placed at the 6 o’clock position.

Sweep Second Hand

A hand that rotates 360 degrees every minute and is centrally mounted in the dial, thus “sweeping” the expanse of the dial every minute. In a Quartz Analog watch this type of hand traverses a 6 degree arc each second.

Swiss Made

The Federation of the Swiss Watch Industry has set standards governing the mark “Swiss Made”.In brief, a watch which is marked “Swiss Made” must contain a “Swiss Movement”, must have been assembled and tested in Switzerland, and must meet minimum values of Swiss part content and Swiss labor.

T

Tachymeter

“Tachy” in Greek means “fast”. A Tachymeter indicates how fast something is going. In a wristwatch, tachymeter markings on the dial of a watch, usually associated with the sweep second hand, relate elapsed time to speed, usually against a measured mile or kilometer. You use the tachymeter dial simply by starting your travel when the second hand is at 12 o’clock. After you have traveled a mile, the position of the second hand shows the speed. For instance, if the second hand is at 6 o’clock (¹/₂ rotation of the dial) after you have traveled a mile the tachymeter marking will show 120, since traveling 1 mile in 30 seconds is equivalent to a speed of 120 miles per hour.

Tourbillon

An escapement which rotates 360 degrees, usually in one minute, in order to average the timekeeping distortion of earth’s gravitational field to 0. “Tourbillon” in French means “whirlwind”. The famous French watchmaker Abraham Louis Breguet invented the tourbillon escapement in the latter part of the 18^th century to improve the accuracy of pocket watches. While tourbillions are beautiful to watch, they are functionally useless in wristwatches.

U

UCT

Abbreviation: Universal Coordinated Time
A standard time system which is based on atomic clocks and which is adjusted (by adding a “leap second”) to account for the gradual slowing down of the earth’s rotation. A leap second was added in 2006.

W

Watch

A small timekeeping device.

Water Resistance

Water resistant markings are on case backs. Watches will withstand water as long as the crystal, crown case, push buttons, and gaskets remain intact.

Markings	Example of Usage
Water resistant	Withstand splashes of water or rain; do not submerge
3 atm/30m/100 ft.	Rain, showering; do not submerge
5 atm/50m/165 ft.	Rain, showering, swimming
10 atm/100m/330ft.	Rain,showering, swimming, sailing, snorkeling, recreational diving
20 atm/100m/330ft.	Rain, showering, swimming, sailing, snorkeling, recreational diving, surfing, white water rafting

Window

Hole in dial through which underlying mechanisms, usually a date wheel, can be seen.

World Time

Watch that shows the current time in selected major cities around the world.

Wristwatch

A watch designed to be worn on the wrist.

Y

Yachtimer

A chronograph watch used specifically for yacht racing.