trilogy vs triplet

trilogy and triplet both are nouns.

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

As nouns, triplet is a hypernym of trilogy; that is, triplet is a word with a broader meaning than trilogy:

trilogy: a set of three literary or dramatic works related in subject or theme
triplet: a set of three similar things considered as a unit

Other hypernyms of trilogy include triad, trio, triple.

trilogy (noun)	triplet (noun)
a set of three literary or dramatic works related in subject or theme	a set of three similar things considered as a unit
	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