terzetto vs threesome

terzetto and threesome both are nouns.

Word	Noun	Adjective	Verb	Adverb
terzetto	Yes	No	No	No
threesome	Yes	No	No	No

As nouns, terzetto and threesome are synonyms defined as:

terzetto and threesome: the cardinal number that is the sum of one and one and one

Other synonyms of terzetto include 3, deuce-ace, III, leash, tercet, ternary, ternion, three, tierce, trey, triad, trine, trinity, trio, triplet, troika.

terzetto (noun)	threesome (noun)
the cardinal number that is the sum of one and one and one	three people considered as a unit
	the cardinal number that is the sum of one and one and one