The largest independent, non-commercial, consumer-oriented resource on the Internet for owners, collectors and enthusiasts of fine wristwatches. Online since 1998.
Search Articles
Table of Contents
Image of the Day

Omega Seamaster Planet Ocean, ref. 2208.50.00, introduced 2005
[image: Omega]
Awards & Rankings

Wristwatch Terminology

Know the difference between a chronometer and a chronograph? Is it good or bad that your watch 'hacks?'

  1. What is the difference between a Chronometer and a Chronograph?
  2. What exactly constitutes a "Swiss Made" watch?
  3. What other watch terminology do I need to know?"

What is the difference between a Chronometer and a Chronograph?

These two similar terms are both used with watches and are easily confused.

The simple answer is that a chronometer is a certified accurate timepiece, a chronograph is a timepiece with stopwatch functions. So for any watch, one, both, or neither terms may apply.

Any watch with stopwatch functions can be called a chronograph. This has nothing to do with any measurement of accuracy, it is merely a statement that the watch has this function.

In watch industry terms, the elapsed time measurement functions of a chronograph are some of the many 'complications' beyond the basic timekeeping functions of a watch mechanism. Even watches with quartz movements may implement these complications through mechanical gears, wheels, and dials. Other watch complications include date indicators, alarms, moon phase displays, multiple time zone features, and other time-related measurements shown with additional hands, windows, or sub-dials on the watch.

The first need for very accurate timepieces came from ships needing precision timekeeping to allow precise celestial navigation. The term chronometer came in to use to describe timepieces accurate enough for ship navigation. In 1973, the Controle Officiel Suisse des Chronometeres (COSC) came in to existence as the official testing and certification control board.

Now, only a watch whose movement has been certified by COSC can be called a chronometer. For a typical men's-sized mechanical watch movement, it must have stayed within -4 to +6 seconds of variation per day during the COSC measurement at various temperatures and positions.

COSC also certifies quartz movements (their standard is +/-0.2 second per day for these). But since quartz movements are inherently very accurate and suffer little to no variation based on position or normal temperature ranges, certification is much less significant to buyers of quartz movement watches. Almost no watchmakers go to the expense to have COSC certify their quartz movements.

A chronometer certificate is not a guarantee of future accuracy. Watch movements that have been certified can get out of adjustment and perform poorly. Movements that were not certified may still exceed the COSC standards--the manufacturer may simply have simply chosen to bypass the expense of the certification process.

What exactly constitutes a "Swiss Made" watch?

Swiss law is very specific on what points of origin and assembly are permissible in watches that are labeled "Swiss Made." In specific, the law:

...requires that the assembly work on the movement (the motor of the watch) and on the watch itself (fitting the movement with the dial, hands and the various parts of the case) should be carried out in Switzerland, along with the final testing of the movement. It also requires that at least 50% of the components of the movement should be manufactured in Switzerland.

So it is permissible for the movements in Swiss watches to contain a minority portion of parts made outside Switzerland. But the majority of movement parts must come from Switzerland AND and the entire movement and watch must be entirely assembled in Switzerland.

The watch casing and separate or detachable items, such as watch bracelets, do not have to be manufactured in Switzerland. But the "foreign" parts must be delivered to Switzerland unassembled, with actual assembly of them into a watch occurring on Swiss soil.

Other provisions allow for watches where the movement meets the criteria, but the watch is assembled outside of Switzerland to be labeled "Swiss Movement" on the dial. The abbreviation "Swiss Movt" is strictly prohibited, because to someone without superior vision or a magnifier, such a dial label could easily be mistaken for reading "Swiss Made."

What other watch terminology do I need to know?

Many calendar watches in professional photographs will have the date set to 8. It has no major significance other than being a nice looking, symmetrical number.

Many watches in professional photographs will have the time set to 10:10, with the second hand likely at 24, 37, or 45. It has no major significance other than the 10:10 being a happy looking presentation of the watch face, This combination, including the placement of the second hand is also intended to ensure none of the hands cross each other or block any of the important information the dial. In rare cases, you will see a complicated watch, such as a chronograph, photographed with the hands in an 'impossible' position--one staged for the photograph, but not possible to occur in the normal operation of the watch.

12 hour versus 24 hour clocks
Most watches and clocks have 12-hour displays even though days are 24 hours long. Only a few rare models have 24 hour dials, though 24 hour display modes on digital watches are pretty common. 'GMT' watches typically have one hand that operates on a 12 hour basis to display local time plus a 24 hour hand to display a second time zone.

Before there were clocks, people used sundials to measure time. Since sundials only work during the half of the day where there is daylight, sundial dials were marked to only show the 12 daylight hours. When mechanical timepieces came into popularity, they typically used the same 12 hour format to be familiar to people used to telling time from sundials. Back then, few people dealt with anything other than local time, so day and night were pretty obvious. It was not until many years later than trans-timezone travel and communication would occur rapidly enough to cause 12/24 hour confusion. By then, the 12-hour clock dial was so prevalent, it remained the standard.

14K gold
555 fine gold is seldom used for fine jewelry outside the USA. Between 1933 and 1974, United States citizens were not allowed to own 18 or 24K in bullion form because of laws put in place in 1933 to prevent hoarding of precious metals (specifically gold and silver) when the US went off the gold standard for currency. Further, the US placed high import taxes on many permissible forms of gold 18K and higher--particularly jewelry and watches. These two factors discouraged the sale of solid and higher carat gold jewelry and watches in the US for many years. It was not until 41 years later (1974) that these laws were repealed and US citizens could again purchase and own 18K and finer gold in bullion form. At the same time, the additional import taxes on many forms of gold were repealed. So many of the 14K gold Swiss watches made for sale in the United States during those years were made of genuine Swiss movements that were assembled in the US into US made gold casings.

555, 750, 925...
an indication of the purity (similar to the Karat rating) of the metal used. The meaning of this number is the parts per thousand of the pure metal in the alloy used. For a more detailed explanation, see Karat below.

Authorized Dealer
a watch seller who is officially sanctioned by the manufacturer. Watches that they sell will have full manufacturer warranties. Also, should you have any difficulties with an authorized dealer, you have the option to get the manufacturer to intervene on your behalf. Also see Unauthorized Dealer below.

refers to mechanical watch movements that wind themselves from the wearer's physical activity. For more detail, see the two types, Bumper Automatic and Rotor Automatic.

the most critical moving part of a mechanical watch movement. This includes the balance wheel that rapidly spins back and forth and the balance lever. The lever is the ratchet mechanism that makes the characteristic 'tick' sound as it converts the balance wheel's motion into the precisely regulated increments of movement that run the watch.

a vague, generic term used to refer to the band that holds a watch on your wrist. The preferred terms are Bracelet or Strap, which clearly describe the two major types.

Battery-less Quartz
also known under various marketing names, including Kinetic (Seiko), Omega-matic (Omega), and Autoquartz (Invicta). Terms for the modern hybrid watch technology of using a quartz movement powered by a small electric current generator operated by a rotor. Electricity generated from the rotor's movement is stored in a capacitor, rechargeable battery, or similar means to keep the watch running. So, like an automatic watch, these also must be worn regularly to keep up their electrical power reserve.

generically, the upper part of the watch body. Specifically, it usually refers to a ring around the outside of the crystal. On jewelry watches, the bezel may contain a ring of diamonds. On sports watches, the bezel may have calibrated markings and the ability to rotate in one or both directions.

a metal link watch band. Similar to a jewelry bracelet, may have a clasp to open it.

Bumper Automatic
a type of watch movement found only in vintage watches. It is similar to the rotor automatic which winds the watch based on the wearer's movements. The difference with the bumper automatic is the weight may have only a 180 degree or less path of movement--hitting a small bumper at each end of its path of travel.

Certified Chronometer
another term for Chronometer. This somewhat redundant phrase is used to make it clear to watch buyers that 'chronometer' is a certification. Also see Chronometer.

a watch or clock movement certified accurate by the Contrôle Officiel Suisse des Chronomètres (Swiss Chronometer Control Board). Also see COSC and the article on Accuracy.

the fastener or catch used to open and close a watch bracelet. Also see Deployant Clasp.

the direction of movement of the hands of a clock. The definition of clockwise came from the way the shadow indicator moves on sundials in the northern hemisphere. When the Europeans and Chinese made mechanical timekeepers, they made the hands move the same way because that was the way people were used to reading time.

is the Contrôle Officiel Suisse des Chronomètres (Swiss Chronometer Control Board). They are the official Swiss agency that certifies all watch movements that bear the internationally recognized and protected status of "Chronometer." Also see Chronometer and the section on Accuracy.

the knob on a watch - often at the 3 o'clock position - used for winding and setting the watch.

the glass front of a watch. Often made of a mineral glass or acrylic, but on many finer watches, it is a synthetic sapphire which is very hard to scratch.

Deployant Clasp
a clasp mechanism for use with watch straps. This allows a leather or other watch strap to operate similar to a watch bracelet. This gives a nicer, more finished appearance than the traditional tang-type buckle on most straps. Sometimes mistakenly called a 'deployment' clasp.

A base watch movement. Often, manufacturers will make custom modifications to the base movement to add complications (features), decorate the movement, and electroplate or upgrade certain parts for added durability.

Gold, Rose Gold, Yellow Gold, and White Gold
The only natural form of gold is yellow gold. But since gold is too soft in its pure form to make jewelry, it is normally made into an alloy by mixing it with other metals. The portion of pure gold to other metals determines the Karat rating. 24K is pure gold. 18K is 75% pure. The exact nature of the other metals used determines the color. A moderate amount of copper in the alloy creates Rose Gold. A moderate amount of palladium and nickel in the alloy turns yellow gold into white gold--by literally washing out the yellow color of the metal.

Gray Market
refers to unauthorized sellers of new watches. For more information, see the major section on Gray Market Watches.

the feature on many mechanical movement watches that stops the second hand when you pull the crown all the way out to set the time. This makes it much easier to set a mechanical watch precisely to the second when synching with a time signal or known accurate clock. Older watches less commonly have this feature. To simulate the hack feature on many watches that don't have it, pull the crown out to the time setting position, then try gently turning the crown backwards. This puts a small amount of back pressure on the watch movement, which may stop the second hand long enough for you to synchronize it with another clock.

A method of shock protection for a wristwatch movement, developed in the 1930's. Other named techniques for shock protection include Parachoc, Kif, Unisafe and Novochoc. Incabloc prevents shock damage by allowing the jeweled balance of the watch to move laterally and vertically within a spring-mounted setting. Incabloc is used by many movements including most modern ETA and Omega movements. See also 'Kif' below.

are elements used in mechanical watches. Usually a very inexpensive form of synthetic ruby, these are used for virtually frictionless pivots or hubs at certain critical places int the watch mechanism. These jewels are worth only pennies and do not add any monetary value to a watch. It is also important to understand that more jewels does not necessarily make a better watch. While too few can certainly be a problem, the exact number needed for optimal performance depends on the specific design and features of the movement. Overall, 17 jewels is the lowest number needed for most standard mechanical watch movements. Others movements that implement different designs, or complications such a chronographs, may use more. But a novice cannot derive useful basis of evaluation or comparison from whether a watch has 17, 21, 25 or more jewels.

Karat or K
an indication of the purity of the metal used, expressed in the number of 1/24th of the pure metal used in the alloy. Metals such as gold are too soft in their pure state use in jewelry, so they are typically made into an alloy with other metals for strength. 24K (equal to 24/24ths) is pure metal. 18K is 18 parts pure metal mixed with 6 parts of other metals. That translates to 18/24=0.750, which is 75% pure, or 750 parts per thousand.

Gold is often used in 18K (750 fine), 14K (555 fine), and occasionally 10K (425 fine). Silver and platinum are harder in their natural form, so are usually used at 22K (925 or 950 fine) or 24K (999 fine). Also see the entries above for Gold and 555, 750, 925.

the one or two loops included on watch straps, used to help hold any extra part of the strap protruding past the buckle.

A method of shock protection for a wristwatch movement, developed in the 1930's. Other named techniques for shock protection include Parachoc, Incabloc, Unisafe and Novochoc. Kif is the shock protection system used several watch makers, including Rolex. See also 'Incabloc' above.

the four protrusions on a typical watch case used to attach a bracelet or strap.

is pretty much self explanatory--it refers to a watch movement that you have to manually wind it every day or two to keep it running. This is the oldest method of powering a watch. While much less common today, manual-wind watches are still available from a number of finer watch manufacturers.

Minute Repeater
a special complication found on a few very high end mechanical watches and some more affordable quartz watches. On the major quarters of the hour, or when activated by the wearer, the watch chimes the current time. The minute-repeater chiming pattern uses a mid-note for each hour, followed by a high-mid note pair for each quarter hour, and if chiming a time between the quarters, adds a high-note for each minute past the quarter hour. So a time like 2:22 would chime as: "dong, dong, ding-dong, ding, ding, ding, ding, ding, ding, ding."

NOS or New Old Stock
items that are older but still technically considered new as they have never been used or sold to a customer. Often these are unsold watches, watch bracelets or other parts that have been in a store's inventory or warehouse for a long time--often for years or decades after that model has been discontinued by the manufacturer. Sometimes improperly used by watch sellers on auction sites to describe watches that are older but still look vaguely in 'like new' condition.

Power Reserve
a measure of the amount of time a watch will run after being fully powered or wound, with no additional power input. Normally, this means when a mechanical watch is fully wound or a quartz watch has a brand new battery. Many modern mechanical watches have a power reserve of 40 hours. Power reserve also applies to battery-less quartz watches, which may have power reserves from 40 hours to 6 months. On battery-operated quartz watches, the term is sometimes used to refer to the expected battery life--typically 12 to 32 months. For more information, see the Fine Wristwatch Owner's Guide section on Why does my automatic watch run down in less than its stated Power Reserve?.

Rotor Automatic
the most common form of automatic watch, and pretty much the only type manufactured today. In it, a weight inside the back of the watch has a 360 degree free path of rotation. Activity of the wearer causes the rotor to move. Its movement in one or both directions (depending on the exact watch movement) winds the watch.

see Automatic above, which is the preferred term.

a watch band made of cloth, rubber, leather or other non-metal material.

Superlative Chronometer
another term for Chronometer. The use of the word Superlative in front of the industry standard term Chronometer is a Rolex trademark to give more panache to their product. But the term Superlative is merely fluff. There is only one grade of chronometer. Any watch bearing the any form of Chronometer designation has been certified by the same agency (COSC) and to the exact same standards as any other Chronometer. So the terms 'Superlative Chronometer' and 'Certified Chronometer' and 'Chronometer' all mean the exact same thing. Also see Chronometer.

a metal with a texture similar to titanium, but a color similar to gold. Used by Omega for the gold-like trim on certain titanium watches. Many of these watches are also available in titanium with real gold trim.

a special complication found on only a few very high end mechanical watches that compensates for the effect of gravity. This eliminates the small variation in watch movement performance based on the position of the watch (face up, face down, on side, etc.).

Unauthorized Dealer
a watch seller who is selling a particular brand of watches, but without being officially sanctioned by the manufacturer. These are typically dealers that buy the watches through indirect, closeout or 'back door' channels. Since they have no direct business relationship with the watch manufacturer, the manufacturer cannot ensure the quality of product or service the dealer provides. Further, any official factory warranties form the manufacturer are voided on watches bought through these unofficial 'back door' dealers. The warranties that such dealers promise are their own warranty coverage, not the manufacturer's factory warranty. Also see Authorized Dealer above.

Watch Winder
a powered device that rotates an automatic watch to keep it wound and running when not on a person's wrist. See the major section Watch Winders for more information.

a term no longer used because it incorrectly implied a more complete resistance to water entry than such watches were actually capable of. See Water Resistant.

Water Resistant
a designation indicating a watch has been tested to resist entry of water into its casing based on static pressure tests. For more information, see the major section on Water Resistance.
Chronocentric and zOwie site design and contents (c) Copyright 1998-2005, Derek Ziglar. All rights reserved. Use of this web site constitutes acceptance of the terms of use. CONTACT | TERMS OF USE | TRANSLATE