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.
      [1913 Webster]

   2. Not possessing reason, irrational; unthinking; as, a brute
      beast; the brute creation.
      [1913 Webster]

            A creature . . . not prone
            And brute as other creatures, but endued
            With sanctity of reason.              --Milton.
      [1913 Webster]

   3. Of, pertaining to, or characteristic of, a brute beast.
      Hence: Brutal; cruel; fierce; ferocious; savage; pitiless;
      as, brute violence. --Macaulay.
      [1913 Webster]

            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.
      [1913 Webster]

            A great brute farmer from Liddesdale. --Sir W.
                                                  Scott.
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   5. Rough; uncivilized; unfeeling. [R.]
      [1913 Webster]

   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.]
   [1913 Webster]

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.
      [1913 Webster]

   2. A brutal person; a savage in heart or manners; as
      unfeeling or coarse person.
      [1913 Webster]

            An ill-natured brute of a husband.    --Franklin.
      [1913 Webster]

   Syn: See Beast.
        [1913 Webster]

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]

Moby Thesaurus II by Grady Ward, 1.0:

165 Moby Thesaurus words for "brute":
   Adamic, Circean, Draconian, Goth, Mafioso, Neanderthal, Tartarean,
   Young Turk, animal, animalian, animalic, animalistic,
   anthropophagite, anthropophagous, atrocious, barbarian, barbaric,
   barbarous, beast, beastlike, beastly, beldam, berserk, berserker,
   bestial, blind, bloodthirsty, bloody, bloody-minded, bodily,
   bomber, brutal, brutalized, brutelike, brutish, cannibal,
   cannibalistic, carnal, carnal-minded, coarse, creature,
   creeping thing, critter, cruel, cruel-hearted, demon, demoniac,
   demoniacal, destroyer, devil, devilish, diabolic, dragon, dull,
   dumb, dumb animal, dumb friend, earthy, fallen, fell, feral,
   ferine, ferocious, fiend, fiendish, fiendlike, fierce, fire-eater,
   firebrand, fleshly, fury, goon, gorilla, gross, gunsel, hardnose,
   hell-raiser, hellcat, hellhound, hellion, hellish, holy terror,
   hood, hoodlum, hothead, hotspur, hyena, incendiary, infernal,
   inhuman, inhumane, insensate, instinctive, instinctual, irrational,
   killer, lapsed, living being, living thing, mad dog, madcap,
   man-eater, material, materialistic, mindless, monster, mugger,
   murderous, nihilist, nonrational, nonspiritual, orgiastic,
   physical, postlapsarian, rapist, revolutionary, ruthless, sadistic,
   sanguinary, sanguineous, satanic, savage, senseless, shark,
   sharkish, she-wolf, slavering, spitfire, subhuman, swinish,
   termagant, terror, terrorist, thoughtless, tiger, tigress, tough,
   tough guy, troglodyte, truculent, ugly customer, unchristian,
   uncivilized, unconscious, unfeeling, unhuman, unintelligent,
   unreasoning, unspiritual, unthinking, vandal, varmint, vicious,
   violent, virago, vixen, wild beast, wild man, witch, wolf, wolfish,
   wrecker, zoic, zooidal, zoologic



The Devil's Dictionary (1881-1906):

BRUTE, n.  See HUSBAND.