pinion: Meaning and Definition of

pin•ion

1. a gear with a small number of teeth, esp. one engaging with a rack or larger gear. See diag. underrack1.
2. a shaft or spindle cut with teeth engaging with a gear.
2. a gear driving a roll in a rolling mill.

pin•ion

1. the distal or terminal segment of the wing of a bird consisting of the carpus, metacarpus, and phalanges.
2. the wing of a bird.
3. a feather.
4. the flight feathers collectively.

1. to cut off the pinion of (a wing) or bind (the wings), as in order to prevent a bird from flying.
2. to disable or restrain (a bird) in such a manner.
3. to bind (a person's arms or hands) so they cannot be used.
4. to disable (someone) in such a manner; shackle.
5. to bind or hold fast, as to a thing: to be pinioned to one's bad habits.