Definition of pinions:
(n) :
(mechanical engineering) The smallest gear in a gear train.
(v) :
To cut off the pinion of a bird’s wing, or otherwise disable or bind its wings, in order to prevent it from flying.
(v) :
To bind the arms of someone, so as to deprive him of their use; to disable by so binding.
(v) :
(transferred sense, figurative) To restrain; to limit.
(n) :
A wing.
(n) :
(ornithology) The joint of a bird's wing farthest from the body.