constraint vs fastening

constraint and fastening both are nouns.

Word	Noun	Adjective	Verb	Adverb
constraint	Yes	No	No	No
fastening	Yes	No	No	No

As nouns, fastening is a hyponym of constraint; that is, fastening is a word with a more specific, narrower meaning than constraint:

constraint (noun)	fastening (noun)
the act of constraining; the threat or use of force to control the thoughts or behavior of others	the act of fastening things together
a device that retards something's motion	restraint that attaches to something or holds something in place
the state of being physically constrained