Source : Webster's Revised Unabridged Dictionary (1913)

Republican \Re*pub"lic*an\ (-l?-kan), a. [F. r['e]publicain.]
   1. Of or pertaining to a republic.

            The Roman emperors were republican magistrates named
            by the senate.                        --Macaulay.

   2. Consonant with the principles of a republic; as,
      republican sentiments or opinions; republican manners.

   {Republican party}. (U.S. Politics)
      (a) An earlier name of the Democratic party when it was
          opposed to the Federal party. Thomas Jefferson was its
          great leader.
      (b) One of the existing great parties. It was organized in
          1856 by a combination of voters from other parties for
          the purpose of opposing the extension of slavery, and
          in 1860 it elected Abraham Lincoln president.

Source : WordNet®

Republican Party
     n : the younger of two major political parties in the United
         States; GOP is an acronym for grand old party [syn: {GOP}]