(n.) Two taken together; a pair or couple; especially two lines of verse that rhyme with each other.

Spenserian stanza antistrophe book both brace burden canto chorus couple distich double harness doublet duad duet duo dyad envoi epode heptastich hexastich line match mates measure monostich octastich octave octet ottava rima pair pentastich quatrain refrain rhyme royal septet sestet set of two sextet span stanza stave strain strophe syllable team tercet terza rima tetrastich the two triplet tristich twain two twosome verse yoke