Professional Jeweler Archive: Timepiece Glossary, Part III

August 2000

Timepieces: Data & Statistics


Timepiece Glossary, Part III

Advanced definitions of terms you may use daily at the sales counter


W e continue our series of definitions of advanced technical terms involving the ever-advancing world of watches.

If you recall, we defined many basic terms last year (Professional Jeweler, May-October 1999). This past June, we began this more involved series because, as retailers sell more sophisticated timepieces, terminology can sometimes move ahead of sales training.

These terms will help you prepare for questions about new chronographs or perpetual calendars you may be selling already. Likewise, knowing the occasional Swiss or French term for a particular function denotes the professional stature you’ve worked hard to achieve.

All definitions are from the Federation of the Swiss Watch Industry, which uses the famed Berner Watch Dictionary as a source.

Glass, Crystal Thin plate of glass or transparent synthetic material that protects dials of watches and clocks.

Hand Indicator, usually of thin, light metal, that moves over a graduated dial or scale. Watches usually have three hands showing the hours, minutes and seconds.

Jewel Bearing, endstone or pallet that reduces friction. They’re generally made of synthetic material, though natural ruby, sapphire or garnet are sometimes used in deluxe watches.

Main Plate Base plate on which all the other parts of a watch movement are mounted.

Mainspring The driving spring of a watch or clock, contained in the barrel.

Manufacture d’Horlogerie French term for a watch factory that produces components (particularly the ébauches) needed to make its products (watches, alarm and desk clocks).

Marine Chronometer A highly accurate mechanical or electronic timekeeper enclosed in a box and used to determine the longitude onboard ship. Marine chronometers with mechanical movements are mounted on gimbals to remain in the horizontal position necessary for precision.

Middle The middle part of the case that holds the movement.

Movement An assembly consisting of the principal elements and mechanisms of a watch or clock, including the winding and setting mechanism, the mainspring, the train, the escapement and the regulating elements. The movement consists of the ébauche, the regulating elements and other components.

Regulating Elements Parts comprising the regulating system (spring balance) and the escapement (escape wheel, lever and roller).

Repeater Watch that strikes the hours with a mechanism operated by a push-piece or bolt. The types of repeaters:

  • Quarter-repeater, which sounds a low note for the hours and a “ding-dong” for each of the quarters.
  • Five-minute repeater, which strikes hours, quarters and five-minute periods after the quarter.
  • Minute-repeater, which strikes the hours, quarters and minutes.
  • Grande sonnerie, which strikes the hours and quarters automatically, repeating when a push-piece is pressed down.
  • Chiming repeater, in which the quarters are struck on three or four gongs of different pitch.

Rotor A half-disc of metal that rotates inside the case of an automatic watch thanks to energy produced by the wearer’s arm movements. Its weight brings it back to the vertical position. Demultiplied by a specially designed device, its rotations continually wind the mainspring.

This quartz movement made by Ronda shows the front view with the hands and the dates.

Copyright © 2001 by Bond Communications