PROPONENT

from WordNet (r) 3.0 (2006)

proponent
    n 1: a person who pleads for a cause or propounds an idea [syn:
         {advocate}, {advocator}, {proponent}, {exponent}]

from The Collaborative International Dictionary of English v.0.48

Proponent \Pro*po"nent\, a. [L. proponens, p. pr.]
   Making proposals; proposing.
   [1913 Webster]

from The Collaborative International Dictionary of English v.0.48

Proponent \Pro*po"nent\, n.
   [1913 Webster]
   1. One who makes a proposal, or lays down a proposition.
      --Dryden.
      [1913 Webster]

   2. (Law) The propounder of a thing.
      [1913 Webster]

from Bouvier's Law Dictionary, Revised 6th Ed (1856)

PROPONENT, eccl. law. One who propounds a telling as "the party proponent 
doth allege and propound." 6 Eng. Ecclesiastical R. 356, n.

from Moby Thesaurus II by Grady Ward, 1.0

27 Moby Thesaurus words for "proponent":
      adherent, advocate, apologete, apologist, apologizer, backer,
      champion, defender, enthusiast, exponent, expounder, friend,
      justifier, partisan, patron, pleader, promoter, proposer,
      spokesman, spokesperson, spokeswoman, subscriber,
      successful advocate, supporter, upholder, vindicator,
      whitewasher

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