# Watch glossary: U, V, W, Z.

UNIDIRECTIONAL ROTATING 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. Because the bezel moves in only one direction, the diver can err only on the side of safety when timing his dive. Many divers' watches are ratcheted, so that they lock into place for greater safety.
UNIVERSAL TIME
The mean solar time of the Greenwich meridian, counted from noon to noon, Often confused with the mean time notion.
VARIATION
In horology the term is usually referred to the variation of the daily rate, i.e. the difference between two daily rates specified by a time interval.
VIBRATION
Movement of a pendulum or other oscillating bodies, limited by two consecutive extreme positions. In an alternate (pendulum or balance) movement, a vibration is a half of an oscillation. The number of hourly vibrations corresponds to the frequency of a watch movement, determined by the mass and diameter of a balance and the elastic force of the balance spring. The number of vibrations per hour (vph) determines the breaking up of time (the "steps of a second hand). For instance, 18,000 vph equals a vibration duration of 1/5 second; in the same way 21,600 vph = 1/6 second; 28,800 vph = 1/8 second; 36,000 vph = 1/10 second. Until the 1950s, wristwatches worked mostly at a frequency of 18,000 vph; later, higher frequencies were adopted to produce a lower percentage of irregularities to the rate. Today, the most common frequency adopted is 28,800 vph, which assures a good precision standard and less lubrication problems than extremely high frequencies, such as 36,000 vph.
WATER RESISTANT or WATERPROOF
A watch whose case is designed in such a way as to resist infiltration by water (3 ATM, or atmospheres, corresponding to a conventional depth of 30 meters; 5 atmospheres, corresponding to a conventional depth of 50 meters.)
WHEEL
Circular element, mostly toothed, combines with an arbor and a pinion to make up a gear. Wheels are normally made of brass, while arbors and pinions are made of steel. The wheels between barrel and escapement make up the so-called train.
WINDING STEM
Element transmitting motion from the crown to the gears governing manual winding and setting.
WINDOW
Aperture in the dial, that allows reading the underlying indication, mainly the date, but also indications concerning a second zone's time or jumping hour.
WORLD TIME
Additional feature of watches provided with a GMT function, displaying the 24 time zones on the dial or bezel, each zone referenced by a city name, providing instantaneous reading of the time of any country.
ZONE
Small additional dial or indicator that may be positioned, or placed off-center on the main dial, used for the display of various functions (e.g. second counters).
ZODIAC
Circular belt with the ecliptic in the middle containing the twelve constellations through which the sun seems to pass in the course of a year.

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## Related Questions:

### whats the rotating outter ring marked 0 through 60 function on my armitron 20/4664sv

The rotating bezel can be used to measure elapsed time. For example, if the time on your watch reads 10.10, align the zero point of the bezel with the minute hand. Now, say the time is 10.40, the minute hand at 8 o'clock will point towards 30 on the bezel, indicating that 30 minutes of time has elapsed since 10.10.

Jan 05, 2014 | Watches

### Hello, I hope that you can tell me some true info about this watch. It is the Invicta Subaqua Noma III (above). Watch descriptions say that the watch has a unidirectional rotating bezel. Is this true?? I can get mine to rotate only one way. Thanks for any help,,,,, William

<P>Thank you for contacting FixYa.</P><P>I dont know much about Invicta, however they have a wonderful website where you can download instructions or contact them.</P><P><A href="http://www.invictawatch.com/welcome/manuals/">http://www.invictawatch.com/welcome/manuals/</A></P><P>Best regards.</P>

Aug 27, 2010 | Invicta Subaqua Noma Iii Chronograph men...

### My TAG Aquaracer bezel moves counterclockwise

Yes, there are solution for that, but you will not be able to solve it yourself as the new part is needed.
That new part is called BEZEL SPRING and it is fitted underneath the bezel.
Bezel spring has special hooks pressed into it and allows to turn the bezel one way only (anticlockwise), at the same time stopping the bezel to turn clockwise.
Another cause can be that the dirt and grime are collected between the bezel and the watch case (this is where the bezel spring is located) and is stopping functionality of the bezel spring by leting the bezel slide over the hooks. This can be fixed by cleaning the watch case in ultrasonic cleaner.
Anyway- if the bezel is rotating on its own, I suggest that the bezel spring is broke and you will need to replace it.
Do not forget to rate, please.

Feb 09, 2009 | Tag Heuer WAF2110.BA0806 Aquaracer...

### Rotating unidirectional bezel malfunction

I have this same problem and sent it to Luminox and they fixed it for just the shipping.

May 15, 2008 | Navy Seal Luminox Watch

### rotating outer ring

It is primarily cosmetic - the bezel was originally designed for diving, military activities or similar where counting down time was critical. Before digital stopwatches etc were built into watches as a feature, what you did as a diver was turn the bezel to the time (say 30 minutes) of air you had left, then the minute hand would travel around the face to the position 0 on the bezel, telling you 30 minutes had passed. You often find compass directions, various job specific calculators etc on bezels also, but unless you need a stopwatch / time reminder and don't have that feature in the watch itself, then it is purely a tradition to include a rotating bezel. The original bezels would have the time markings going the opposite way to the watch face usually, however on many modern watches, they often go the same way, allowing you to see how much time has passed, rather than how much you have left. Hope this clears things up :)

Mar 31, 2007 | Fossil CH2332 Wrist Watch

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