mainspring
Meaning
The principal spring in a mechanical device, especially in a watch or clock, that drives the mechanism.
The most important motivating force or reason for something.
Structure
Usage
The watchmaker carefully replaced the broken mainspring.
Her unwavering faith was the mainspring of her charitable work.
A free press is often considered the mainspring of a healthy democracy.
Etymology
The word 'mainspring' is a transparent compound from two native English elements. 'Main', derived from Old English mægen (power, strength), evolved to denote something primary or principal. 'Spring', from Old English springan (to leap), developed the mechanical sense of an elastic device that "springs" back into shape. The term first appeared in the 16th century to literally name the primary power source in clockwork. Its figurative use, describing a central motivating force, logically extended from this core mechanical function, illustrating how a physical invention provided a metaphor for a driving cause or reason.
Analysis
- main: From Old English mægen meaning "strength, power, force". In this compound, it functions as an adjective meaning "principal" or "most important". - spring: From Old English springan meaning "to leap, burst forth". In this compound, it functions as a noun referring to the mechanical device, a coiled elastic metal that stores energy.