paper fastener vs fastening

paper fastener and fastening both are nouns.

Word	Noun	Adjective	Verb	Adverb
paper fastener	Yes	No	No	No
fastening	Yes	No	No	No

As nouns, fastening is a hypernym of paper fastener; that is, fastening is a word with a broader meaning than paper fastener:

Other hypernyms of paper fastener include fastener, fixing, holdfast.

paper fastener (noun)	fastening (noun)
a fastener for holding a sheet of paper in place	the act of fastening things together
	restraint that attaches to something or holds something in place