butterfly nut vs wing nut

butterfly nut and wing nut both are nouns.

Word	Noun	Adjective	Verb	Adverb
butterfly nut	Yes	No	No	No
wing nut	Yes	No	No	No

As nouns, butterfly nut and wing nut are synonyms defined as:

butterfly nut and wing nut: a threaded nut with winglike projections for thumb and forefinger leverage in turning

Other synonyms of butterfly nut include thumbnut, wing-nut, wing screw.

butterfly nut (noun)	wing nut (noun)
a threaded nut with winglike projections for thumb and forefinger leverage in turning	a threaded nut with winglike projections for thumb and forefinger leverage in turning
	any tree of the genus Pterocarya; fruit is a small winged nutlet; Caucasus to southeastern Asia