The Collaborative International Dictionary of English v.0.48:

paired \paired\ (p[^a]rd), adj.
   1. Organized into compatible pairs; -- used of gloves, socks,
      etc. See pair[1], v. t.

   Syn: mated.
        [WordNet 1.5]

   2. (Botany) Growing in pairs on either side of a stem; -- of
      leaves etc. alternate

   Syn: opposite.
        [WordNet 1.5]

   3. Mated sexually.
      [WordNet 1.5]

The Collaborative International Dictionary of English v.0.48:

Pair \Pair\, v. i. [imp. & p. p. Paired; p. pr. & vb. n.
   Pairing.]
   1. To be joined in pairs; to couple; to mate, as for
      breeding.
      [1913 Webster]

   2. To suit; to fit, as a counterpart.
      [1913 Webster]

            My heart was made to fit and pair with thine.
                                                  --Rowe.
      [1913 Webster]

   3. Same as To pair off. See phrase below.
      [1913 Webster]

   To pair off, to separate from a group in pairs or couples;
      specif. (Parliamentary Cant), to agree with one of the
      opposite party or opinion to abstain from voting on
      specified questions or issues. See Pair, n., 6.
      [1913 Webster]

WordNet (r) 3.0 (2006):

paired
    adj 1: used of gloves, socks, etc. [syn: mated, paired]
    2: of leaves etc; growing in pairs on either side of a stem;
       "opposite leaves" [syn: opposite, paired] [ant:
       alternate]
    3: mated sexually

Moby Thesaurus II by Grady Ward, 1.0:

76 Moby Thesaurus words for "paired":
   accessory, accompanying, affiliate, affiliated, allied, assembled,
   associate, associated, attendant, attending, banded together,
   biconjugate, bigeminate, bijugate, bound, bracketed, cabalistic,
   coincident, collateral, collected, combined, concomitant,
   concurrent, confederate, confederated, conjoined, conjoint,
   conjugate, conjugated, connected, conspiratorial, copulate,
   corporate, correlative, coupled, double, dual, enleagued, federate,
   federated, fellow, gathered, hand-in-glove, hand-in-hand,
   in cahoots, in league, in partnership, in with, incorporated,
   integrated, intimate, joined, joint, knotted, leagued, linked,
   married, matched, mated, merged, mutual, one, parallel, partnered,
   partners with, simultaneous, spliced, teamed, tied, twin,
   undivided, united, unseparated, wed, wedded, yoked