duet vs terpsichore

duet and terpsichore both are nouns.

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

As nouns, terpsichore is a hypernym of duet; that is, terpsichore is a word with a broader meaning than duet:

duet: (ballet) a dance for two people (usually a ballerina and a danseur noble)
terpsichore: taking a series of rhythmical steps (and movements) in time to music

Other hypernyms of duet include dance, dancing, saltation.

duet (noun)	terpsichore (noun)
(ballet) a dance for two people (usually a ballerina and a danseur noble)	taking a series of rhythmical steps (and movements) in time to music
a musical composition for two performers
a pair who associate with one another
two performers or singers who perform together
two items of the same kind