hairspring [
'hɛr`sprɪŋ]
n. 细弹簧, 游丝
hairspring[ noun ]
a fine spiral spring that regulates the movement of the balance wheel in a timepiece
<noun.artifact>
Hairspring \Hair"spring`\ (-spr[i^]ng`), n. (Horology)
The slender recoil spring which regulates the motion of the
balance in a timepiece.