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duo vs. duet

duo
[doo-oh, dyoo-oh] / ˈdu oʊ, ˈdyu oʊ /

noun

plural

duos
  1. Music. duet.

  2. two persons commonly associated with each other; couple.

  3. two animals or objects of the same sort; two things ordinarily placed or found together; a pair.

    a duo of lovebirds.

[doo-et, dyoo-] / duˈɛt, dyu- /

noun

  1. a musical composition for two voices or instruments.