Chainset

Part of speech: noun

Definitions

1. The assembly of front chainrings that a bicycle's pedal crank turns, which drives the chain to the rear wheel
2. A cluster of toothed rings fitted to a bicycle's crank, through which pedalling power is transferred by the chain
3. The gearing unit on a bike made up of front chainwheels that work together with the chain to propel the machine

Etymology: "Chainset" is a compound of "chain" and "set": the chain set is the assembly of chainrings bolted to the crank on the front of a bicycle, over which the drive chain runs. The word is a plain, transparent formation rather than a story with a famous coiner or a surprising shift in meaning. "Chain" comes from Old French "chaene," ultimately from Latin "catena," meaning "a series of links," while "set" is the ordinary English noun for a group of parts or things that belong together, as in a tea set or a set of tools. Put together, the two parts describe the bicycle component literally: a set of chains' toothed wheels, or chainrings, working as one unit. The compound reflects the way cycling vocabulary often names parts by their function, so the name stays close to the mechanism it describes.