completion vs pass completion

completion and pass completion both are nouns.

Word	Noun	Adjective	Verb	Adverb
completion	Yes	No	No	No
pass completion	Yes	No	No	No

As nouns, completion and pass completion are synonyms defined as:

completion and pass completion: (American football) a successful forward pass in football

completion (noun)	pass completion (noun)
a concluding action	(American football) a successful forward pass in football
(American football) a successful forward pass in football