The Collaborative International Dictionary of English v.0.48:

Peer \Peer\, n. [OE. per, OF. per, F. pair, fr. L. par equal.
   Cf. Apparel, Pair, Par, n., Umpire.]
   1. One of the same rank, quality, endowments, character,
      etc.; an equal; a match; a mate.
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            In song he never had his peer.        --Dryden.
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            Shall they consort only with their peers? --I.
                                                  Taylor.
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   2. A comrade; a companion; a fellow; an associate.
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            He all his peers in beauty did surpass. --Spenser.
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   3. A nobleman; a member of one of the five degrees of the
      British nobility, namely, duke, marquis, earl, viscount,
      baron; as, a peer of the realm.
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            A noble peer of mickle trust and power. --Milton.
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   House of Peers, The Peers, the British House of Lords.
      See Parliament.

   Spiritual peers, the bishops and archibishops, or lords
      spiritual, who sit in the House of Lords.
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