triplet vs three

triplet and three both are nouns.

Word	Noun	Adjective	Verb	Adverb
triplet	Yes	No	No	No
three	Yes	Yes	No	No

As nouns, triplet and three are synonyms defined as:

triplet and three: the cardinal number that is the sum of one and one and one

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

triplet (noun)	three (noun)
a set of three similar things considered as a unit	one of four playing cards in a deck having three pips
one of three offspring born at the same time from the same pregnancy	the cardinal number that is the sum of one and one and one
the cardinal number that is the sum of one and one and one

triplet (adjective)	three (adjective)
	being one more than two