clasp vs holdfast

clasp and holdfast both are nouns.

Word	Noun	Adjective	Verb	Adverb
clasp	Yes	No	Yes	No
holdfast	Yes	No	No	No

As nouns, holdfast is a hypernym of clasp; that is, holdfast is a word with a broader meaning than clasp:

clasp: a fastener (as a buckle or hook) that is used to hold two things together
holdfast: restraint that attaches to something or holds something in place

Other hypernyms of clasp include fastener, fastening, fixing.

clasp (noun)	holdfast (noun)
the act of grasping	restraint that attaches to something or holds something in place
a fastener (as a buckle or hook) that is used to hold two things together

clasp (verb)	holdfast (verb)
hold firmly and tightly
grasp firmly
fasten with a buckle or buckles
fasten with or as if with a brooch