duet vs couple

duet and couple both are nouns.

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

As nouns, duet and couple are synonyms defined as:

Other synonyms of duet include duo, twosome.

As nouns, duet and couple are synonyms defined as:

Other synonyms of duet include brace, couplet, distich, duad, duo, dyad, pair, span, twain, twosome, yoke.

duet (noun)	couple (noun)
(ballet) a dance for two people (usually a ballerina and a danseur noble)	a pair who associate with one another
a musical composition for two performers	a pair of people who live together
a pair who associate with one another	(physics) something joined by two equal and opposite forces that act along parallel lines
two performers or singers who perform together	two items of the same kind
two items of the same kind	a small indefinite number

duet (verb)	couple (verb)
	engage in sexual intercourse
	link together
	bring two objects, ideas, or people together
	form a pair or pairs