Watch Terms (A - B)
alarm - A feature of a watch that produces a sound at a pre-set time.
analog - Time is displayed on a dial with the use of hands to indicate the time.
anodized - A very hard, ceramic coating on aluminum created by an electrolytic process. Various colors may be produced using this coating process.
anti-magnetic - A watch that is resistant to magnetism. A term used to describe the use of non-magnetic materials used in the parts of a watch most affected by magnetization (balance wheel, balance spring and escapement).
antiquarian horologist - A person who practices the art and science of horology, with specific or specialized interest in the study of antique timepieces.
aperture - Small open windows on the dial of a watch used for displaying certain indications, such as day, date, month, hours, minutes, etc.
Arabic numerals - A style of numerals commonly used on watch dials (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12).
arbor - An axis or shaft supporting a moving part such as a wheel or lever.
ATM (atmosphere) - The waterproof pressure ratings of a watch. A watch rated to One Atmosphere would be waterproof to 10 Meters or 30 Feet.
atmosphere (ATM) - The waterproof pressure ratings of a watch. A watch rated to One Atmosphere would be waterproof to 10 Meters or 30 Feet.
automatic mechanical wind - A watch which has mechanical moving parts and winds its mainspring automatically using an internal rotor system.
automatic winding - The watch mainspring is wound automatically by a device inside the movement which rotates due to normal wrist motion while wearing the watch.
baguette - A diamond or gem cut in the shape of a narrow rectangle.
balance - A series of internal parts known as the balance assembly. Oscillating back and forth governs or controls the watch escapement of power, dividing each swing or oscillation of the balance into two equal parts of time.
balance cock - An internal bridge that supports the balance assembly in position.
balance spring - An internal part of a watch which controls the balance wheel oscillations. Due to its size, it is sometimes referred to as a hairspring.
balance staff - The axle or shaft of the balance wheel.
balance wheel - A component of the balance assembly comprised of the balance wheel, hairspring, balance weights, rollers, roller jewels and staff. This assembly controls or governs the escapement and oscillation or time rate of the movement.
barrel - A cylindrical drum-shaped machine part holding the mainspring that powers the watch.
beat - The sound of a watch "ticking," usually about 1/5 of a second. The escape wheel striking the pallets produces the sound.
bezel - A frame or ring which holds the crystal of a watch.
bracelet - A type of metal attachment designed for securing a watch to the wrist.
Braille watch - A watch designed especially for sight-impaired individuals. There is no crystal over the dial. It is fitted with protrusions in place of normal numerals so the characters and hands may be touched by hand.
bridge - An internal part of the watch movement that has two supports. These help make up the frame of the movement that holds parts together.
bubble back - A slang term given to the first style of automatic winding watch made by the Rolex Watch Co. due to its larger than normal "bowed out" or "bubble style" case back.
buttons - External pieces mounted on the outside edge of a watch case used to activate various functions of a watch, such as the chronograph and alarm features.