ETYM Old Fren. pignon a pen, French, gable, pinion; cf. Spanish pińon pinion; from Latin pinna pinnacle, feather, wing. Related to Pin a peg, and cf. Pen a feather, Pennat, Pennon.
A gear with a small number of teeth designed to mesh with a larger wheel or rack.
Small wheel with teethwing; last joint of a wing; outermost flight feather.
ETYM Etymology uncertain.
1. Has teeth on the rims to pull film or paper through.
2. Thin wheel with teeth that engage with a chain; SYN. sprocket wheel.