pinion (n.1) Look up pinion at Dictionary.com
"wing joint, segment of a bird's wing," mid-15c., from Old French pignon "wing-feather, wing, pinion" (c.1400), from Vulgar Latin *pinnionem (nominative *pinnio), augmentative of Latin pinna "wing" (see pin (n.)).
pinion (n.2) Look up pinion at Dictionary.com
"small wheel with teeth to gear with a larger one" (as in rack and pinion), 1650s, from French pignon "pinion" (16c.), literally "gable," from Old French pignon "pointed gable, summit," from Vulgar Latin *pinnionem, augmentative of Latin pinna "battlement, pinnacle" (see pin (n.)).
pinion (v.) Look up pinion at Dictionary.com
"disable by binding the arms," 1550s, older in English than literal sense "cut or bind the pinions (of a bird's wing) to prevent flying" (1570s); from pinion (n.1). Related: Pinioned.