noun (n)

• two items of the same kind(noun.quantity)

  Synonym:
  brace, couple, distich, duad, duet, duo, dyad, pair, span, twain, twosome, yoke
  

  source: wordnet30
• a stanza consisting of two successive lines of verse; usually rhymed(noun.communication)

  source: wordnet30
• Two taken together; a pair or couple; especially two lines of verse that rhyme with each other.(noun)

  source: webster1913