The Collaborative International Dictionary of English v.0.48:

Brute \Brute\, a. [F. brut, nasc., brute, fem., raw, rough,
   rude, brutish, L. brutus stupid, irrational: cf. It. & Sp.
   bruto.]
   1. Not having sensation; senseless; inanimate; unconscious;
      without intelligence or volition; as, the brute earth; the
      brute powers of nature.
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   2. Not possessing reason, irrational; unthinking; as, a brute
      beast; the brute creation.
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            A creature . . . not prone
            And brute as other creatures, but endued
            With sanctity of reason.              --Milton.
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   3. Of, pertaining to, or characteristic of, a brute beast.
      Hence: Brutal; cruel; fierce; ferocious; savage; pitiless;
      as, brute violence. --Macaulay.
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            The influence of capital and mere brute labor.
                                                  --Playfair.
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   4. Having the physical powers predominating over the mental;
      coarse; unpolished; unintelligent.
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            A great brute farmer from Liddesdale. --Sir W.
                                                  Scott.
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   5. Rough; uncivilized; unfeeling. [R.]
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   brute force, The application of predominantly physical
      effort to achieve a goal that could be accomplished with
      less effort if more carefully considered. Figuratively,
      repetitive or strenuous application of an obvious or
      simple tactic, as contrasted with a more clever stratagem
      achieving the same goal with less effort; -- as, the first
      prime numbers were discovered by the brute force
      repetition of the Sieve of Eratosthenes.
      [PJC]

The Collaborative International Dictionary of English v.0.48:

Brute \Brute\, v. t. [For bruit.]
   To report; to bruit. [Obs.]
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The Collaborative International Dictionary of English v.0.48:

Brute \Brute\, n.
   1. An animal destitute of human reason; any animal not human;
      esp. a quadruped; a beast.
      [1913 Webster]

            Brutes may be considered as either a["e]rial,
            terrestrial, aquatic, or amphibious.  --Locke.
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   2. A brutal person; a savage in heart or manners; as
      unfeeling or coarse person.
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            An ill-natured brute of a husband.    --Franklin.
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   Syn: See Beast.
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WordNet (r) 3.0 (2006):

brute
    adj 1: resembling a beast; showing lack of human sensibility;
           "beastly desires"; "a bestial nature"; "brute force"; "a
           dull and brutish man"; "bestial treatment of prisoners"
           [syn: beastly, bestial, brute(a), brutish,
           brutal]
    n 1: a cruelly rapacious person [syn: beast, wolf, savage,
         brute, wildcat]
    2: a living organism characterized by voluntary movement [syn:
       animal, animate being, beast, brute, creature,
       fauna]

The Devil's Dictionary (1881-1906):

BRUTE, n.  See HUSBAND.