Noun duo has 4 senses
- couple, pair, twosome, twain, brace, span, yoke, couplet, distich, duo, duet, dyad, duad - two items of the same kind
--1 is a kind of two, 2, II, deuce
--1 has particulars: doubleton
- duet, duette, duo - two performers or singers who perform together
--2 is a kind of musical organization, musical organisation, musical group
--2 has particulars: Laurel and Hardy
- couple, twosome, duo, duet - a pair who associate with one another; "the engaged couple"; "an inseparable twosome"
--3 is a kind of pair
--3 has particulars: same-sex marriage
- duet, duette, duo - a musical composition for two performers
--4 is a kind of musical composition, opus, composition, piece, piece of music
--4 has parts: primo; secondo
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