- a fixed end of a spiral hairspring, consisting of an upwardly and inwardly bent continuation of the outermost coil of the spring: used to offset the asymmetry of the common spiral spring when tight, which impairs isochronism.
- a hairspring having such a fixed end.
Origin of overcoil
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for overcoil
Used in chronometers and other fine time pieces where the spring is an overcoil.Time Telling through the Ages
Harry Chase Brearley