The Collaborative International Dictionary of English v.0.48:

Republic \Re*pub"lic\ (r?-p?b"l?k), n. [F. r['e]publique, L.
   respublica commonwealth; res a thing, an affair + publicus,
   publica, public. See Real, a., and Public.]
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   1. Common weal. [Obs.] --B. Jonson.
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   2. A state in which the sovereign power resides in the whole
      body of the people, and is exercised by representatives
      elected by them; a commonwealth. Cf. Democracy, 2.
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   Note: In some ancient states called republics the sovereign
         power was exercised by an hereditary aristocracy or a
         privileged few, constituting a government now
         distinctively called an aristocracy. In some there was
         a division of authority between an aristocracy and the
         whole body of the people except slaves. No existing
         republic recognizes an exclusive privilege of any class
         to govern, or tolerates the institution of slavery.
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   Republic of letters, The collective body of literary or
      learned men.
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