noun
pinion
PIN-yun/pˈɪnjʌn/
A small gear that engages with a larger gear or rack.
The pinion turns the larger gear inside the clock.
Etymology
French pignon meant a pointed gable and came to name a small toothed wheel. English pinion carries the mechanical use of this originally architectural term.
In context
the drill press functions on what's called a rack and pinion system so you've got a really big hand wheel over here driving a tiny little pinion gear
More examples
- As the pinion rotates, the rack slides sideways.
- A broken tooth on the pinion causes the mechanism to jam.
- The mechanic replaces two worn pinions in the gearbox.
Forms
pinion · pinions
Similar words
- gear
- A broader term for toothed wheels of any size.
- cogwheel
- Names a toothed wheel without specifying its size or partner.