- 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 - couple, twosome, duo, duet - a pair who associate with one another; "the engaged couple"; "an inseparable twosome"
--2 is a kind of pair
--2 has particulars: same-sex marriage