The Collaborative International Dictionary of English v.0.48:

Presbyter \Pres"by*ter\, n. [L. an elder, fr. Gr. ?. See
   Priest.]
   [1913 Webster]
   1. An elder in the early Christian church. See 2d Citation
      under Bishop, n., 1.
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   2. (Ch. of Eng. & Prot. Epis. Ch.) One ordained to the second
      order in the ministry; -- called also priest.
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            I rather term the one sort presbyter than priest.
                                                  --Hooker.
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            New presbyter is but old priest writ large.
                                                  --Milton.
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   3. (Presbyterian Ch.) A member of a presbytery whether lay or
      clerical.
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   4. A Presbyterian. [Obs.] --Hudibras.
      [1913 Webster]

WordNet (r) 3.0 (2006):

presbyter
    n 1: an elder in the Presbyterian Church