wiggle nail vs holdfast

wiggle nail and holdfast both are nouns.

Word	Noun	Adjective	Verb	Adverb
wiggle nail	Yes	No	No	No
holdfast	Yes	No	No	No

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

wiggle nail: a small strip of corrugated steel with sharp points on one side; hammered across wood joints in rough carpentry
holdfast: restraint that attaches to something or holds something in place

Other hypernyms of wiggle nail include fastener, fastening, fixing.

wiggle nail (noun)	holdfast (noun)
a small strip of corrugated steel with sharp points on one side; hammered across wood joints in rough carpentry	restraint that attaches to something or holds something in place