pennon vs pinion

pennon and pinion both are nouns.

Word	Noun	Adjective	Verb	Adverb
pennon	Yes	No	No	No
pinion	Yes	No	Yes	No

As nouns, pennon and pinion are synonyms defined as:

pennon (noun)	pinion (noun)
wing of a bird	wing of a bird
a long flag; often tapering	any of the larger wing or tail feathers of a bird
	a gear with a small number of teeth designed to mesh with a larger wheel or rack

pennon (verb)	pinion (verb)
	cut the wings off (of birds)
	bind the arms of