composition vs duet

composition and duet both are nouns.

Word	Noun	Adjective	Verb	Adverb
composition	Yes	No	No	No
duet	Yes	No	No	No

As nouns, duet is a hyponym of composition; that is, duet is a word with a more specific, narrower meaning than composition:

composition (noun)	duet (noun)
the act of creating written works	(ballet) a dance for two people (usually a ballerina and a danseur noble)
musical creation	a musical composition for two performers
something that is created by arranging several things to form a unified whole	a pair who associate with one another
the way in which someone or something is composed	two performers or singers who perform together
the spatial property resulting from the arrangement of parts in relation to each other and to the whole	two items of the same kind
an essay (especially one written as an assignment)
a musical work that has been created
art and technique of printing with movable type
a mixture of ingredients