hairspring

American  

[hair-spring] / ˈhɛərˌsprɪŋ /

noun

Horology.

1. a fine, usually spiral, spring used for oscillating the balance of a timepiece.

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hairspring British  

/ ˈhɛəˌsprɪŋ /

noun

1. horology a very fine spiral spring in some timepieces, which, in combination with the balance wheel, controls the timekeeping

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Etymology

Origin of hairspring

First recorded in 1820–30; hair + spring

Example Sentences

However, Shapiro said, the production version of Resurgence will include a hairspring and bearings made in America.

From Los Angeles Times • May 22, 2023

Its hairspring, mainspring, ruby bearings and a few other parts were sourced from Switzerland.

From Los Angeles Times • May 22, 2023

It is intended to be the first member of a family of movements incorporating both the DIAMonSIL escapement and an adjustable oscillator fitted with a silicium hairspring.

From New York Times • Nov. 23, 2012

Since the 17th century they have depended on a delicate hairspring that keeps a balance wheel turning backward and forward at a regular rate.

From Time Magazine Archive

We refer to arranging and disposing of the impulse of the escape wheel to meet the resistance of the hairspring.

From Watch and Clock Escapements A Complete Study in Theory and Practice of the Lever, Cylinder and Chronometer Escapements, Together with a Brief Account of the Origin and Evolution of the Escapement in Horology by Anonymous