pinion in WordNet English dictionary

1. any of the larger wing or tail feathers of a bird
   flight feather  pinion  quill  quill feather 
   
2. wing of a bird
   pennon  pinion 
   
3. a gear with a small number of teeth designed to mesh with a larger wheel or rack
   pinion 
   

1. cut the wings off (of birds)
   pinion 
   
2. bind the arms of
   pinion  shackle