R
Rattrapante (Flyback) Chronograph
A chronograph with an additional hand that moves with the second hand but, can be stopped independently to measure an interval and can then fly back to catch up with the other hand. This is useful for capturing lap times without losing the ability to capture the finish time.
Ratchet Bezel Ring
A bezel ring that can either turn one way (counter-clockwise) or both ways and generally clicks into place.
Register
Another name for a subdial; this is usually a dial within the main dial of a watch.
Repeater
A device that chimes the time when the wearer pushes a button.
Retrograde
Used to describe a pointer hand on a watch dial, which returns to zero at the end of a prescribed period. For example a watch may have retrograde date - in this case the hand moves up a scale a day at a time, pointing to the current date - when it reaches 31 it will spring back to 1
Rhodium Plated
Protective coating of metal with a thin layer of rhodium--a hard, brittle metal which does not oxidize and is malleable only when red hot.
Rose (or Pink) Gold
A softly hued gold that contains the same metals as yellow gold but with a higher concentration of copper in the alloy.
Rotating Bezel
A bezel that can be turned to perform various functions.
Rotor
The part that rotates in automatic (self winding) movements and winds the main spring.
S
Sapphire Crystal
Highest quality transparent that is scratch resistant under normal conditions.
Sapphlex Crystal (Seiko Watches)
Highly scratch resistant crystal created by the fusion of sapphire and mineral glass crystal.
Screw-Down Locking Crown
A crown that aids water resistance by sealing to the case of the watch.
Second Time Zone Indicator
An additional dial that can be set to the time in another time zone. It lets the wearer keep track of local time and the time in another country simultaneously.
Self-Winding
This term refers to a mechanically powered watch that is wound by the motion of the wearer's arm rather than through turning the winding stem.
Shock Resistance
Specified on a watchcase, it means that a watch can withstand normal wear and tear, even during strenuous sport activities.
Slide Rule Bezel
A rotating bezel around the outside edge of the watch case that is printed with a logarithmic scale and assorted other scales and is used in conjunction with fixed rules of mathematics to perform general mathematical calculations or navigational computations.
Solar-powered
A type of quartz movement where the batteries are recharged via solar panels on the watch face. They have a power reserve so they can run even in the dark.
Solar Tech
Solar powered quartz watch. This technology provides the accuracy of quartz, without the inconvenience and cost of regular battery changes.
Split Second
A feature on a chronograph that actually is two hands, one a flyback, the other a regular hand. To time laps or different finishing times, the wearer can stop the fly backhand independently while the regular hand keeps moving.
Stainless Steel
An extremely durable metal alloy that is virtually immune to rust, discoloration, and corrosion; it can be highly polished, thus resembling a precious metal. Because of its strength, stainless steel is often used even on case backs on watches made of other metals.
Sterling Silver
A white and highly reflective precious metal. Sterling refers to silver that is 92.5 percent pure, which should be stamped on the metal, sometimes accompanied by the initials of the designer or country of origin as a hallmark. Although less durable than stainless steel and other precious metals, sterling silver is often employed in watches that coordinate or look like sterling jewelry. A protective coating may be added to prevent tarnish.
Stopwatch
A watch with a second hand that measures intervals of time. When a stopwatch is incorporated into a standard watch, both the stopwatch function and the timepiece are referred to as a "chronograph."
Strap
A watchband made of leather, plastic, fabric or other non-metal material.
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.
Swiss A.O.S.C. (Certificate of Origin)
A mark identifying a watch that is assembled in Switzerland with components of Swiss origin, primarily used in Bedat watches.
T
Tachometer /Tachymeter
Common feature in chronograph watches. Measures the speed over a predefined distance.
Tank Watch
A rectangular watch with heavier bars on either side of the dial. Inspired by the tank tracks of World War I and first created by Louis Cartier.
Tantalum
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.
Telemeter
A watch function that finds the distance of an object from the wearer by measuring how long it takes sound to travel the distance.
Titanium
The "space age" metal, often with a silvery-gray appearance. Because it is 30 percent stronger and nearly 50 percent lighter than steel it has been increasingly used in watch making, especially sport watch styles. Its resistance to salt water corrosion makes it particularly useful in diver's watches. Since it can be scratched fairly easily, some manufacturers use a patented-coating to resist scratching.
Tonneau Watch
A watch with a barrel-shaped watchcase and two convex sides.
U
Unidirectional Rotating Bezel/Unidirectional Turning Bezel
An elapsed time rotating bezel, often found on divers watches, that moves only in a counterclockwise direction. It is designed to prevent a diver who has unwittingly knocked the bezel off its original position from overestimating his remaining air supply.
UTC
Universal Time Coordinated. A universal time based on the Greenwich Meridian used by the military and in aviation. Greenwich Mean Time (GMT) can be considered approximately equivalent to Universal Time Coordinated (UTC). GMT as such is now obsolete however, being replaced by UTC. Using this timezone/standard avoids errors and problems associated with different time zones and summer times operational in different countries.
W
Watch Winder/Watch Winding Case/Watch Rotor/Watch Rotators
A watch winder is a mechanical devise used to maintain the winding on an Automatic Watch. Automatic watches require constant wearing or they need to be placed in a watch winder box to maintain the winding and settings of the automatic watch. A watch winder allows you to own more than one automatic watch and not have to worry about resetting the time on any of them.
Waterproof
An illegal and misused term: No watch is fully 100 percent waterproof.
Water Resistance
Describes the level of protection a watch has from water damage. .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, i.e. 50 meters (165 feet) or more on most sport watches. Below 200 meters, the watch may be used for skin diving and even scuba diving depending upon the indicated depths.
Watches come in different water resistant depths and diver's depths:
Water resistant: Will withstand splashes of water or rain but should not be worn while swimming or diving.
Water tested to 50 meters (165 feet): Suitable for showering or swimming in shallow water.
Water tested to 100 meters (330 feet): Suitable for swimming or snorkeling.
Water tested to 150 meters (500 feet): Suitable for snorkeling.
Water tested to 200 meters (660 feet): Suitable for skin diving.
Diver's to 150 meters: Meets ISO Standards and is suitable for scuba diving.
Diver's to 200 meters: Meets ISO Standards and is suitable for scuba diving.
White Gold
Created from yellow gold by incorporating either nickel or palladium to the alloy to achieve a white color. Most watches made of white gold will be 18k.
Winding
Operation consisting of tightening the mainspring of a watch. This can be done by hand (by the crown) or automatically (by a rotor, which is caused to swing by the movements of the wearer's arm).
Winding Stem
The button on the right side of the watchcase used to wind the mainspring. Also called a "crown."
World Time Dial
A dial, usually on the outer edge of the watch face, which tells the time in up to 24 time zones around the world.
Y
Yacht Timer
A countdown timer that sounds warning signals during the countdown for a boat race.
Yellow Gold
The traditionally popular gold. Yellow gold watches may be found in 14k or, as found from most European manufacturers, 18k.

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