seconder

from WordNet (r) 3.0 (2006)

seconder
    n 1: someone who endorses a motion or petition as a necessary
         preliminary to a discussion or vote

from The Collaborative International Dictionary of English v.0.48

Seconder \Sec"ond*er\, n.
   One who seconds[3] or supports what another attempts,
   affirms, moves, or proposes; as, the seconder of an
   enterprise or of a motion.
   [1913 Webster]

from Moby Thesaurus II by Grady Ward, 1.0

40 Moby Thesaurus words for "seconder":
      Maecenas, abettor, admirer, advocate, aficionado, angel, apologist,
      backer, buff, champion, defender, dependence, encourager, endorser,
      exponent, fan, favorer, friend at court, lover, mainstay,
      maintainer, paranymph, partisan, patron, promoter, protagonist,
      reliance, second, sectary, sider, sponsor, stalwart, standby,
      support, supporter, sustainer, sympathizer, upholder, votary,
      well-wisher

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