The Collaborative International Dictionary of English v.0.48:

Barbaric \Bar*bar"ic\ (b[aum]r*b[a^]r"[i^]k), a. [L. barbaricus
   foreign, barbaric, Gr. barbariko`s.]
   1. Of, or from, barbarian nations; foreign; -- often with
      reference to barbarous nations of east. "Barbaric pearl
      and gold." --Milton.
      [1913 Webster]

   2. Of or pertaining to, or resembling, an uncivilized person
      or people; barbarous; barbarian; destitute of refinement.
      "Wild, barbaric music." --Sir W. Scott.
      [1913 Webster]

WordNet (r) 3.0 (2006):

barbaric
    adj 1: without civilizing influences; "barbarian invaders";
           "barbaric practices"; "a savage people"; "fighting is
           crude and uncivilized especially if the weapons are
           efficient"-Margaret Meade; "wild tribes" [syn:
           barbarian, barbaric, savage, uncivilized,
           uncivilised, wild]
    2: unrestrained and crudely rich; "barbaric use of color or
       ornament"

Moby Thesaurus II by Grady Ward, 1.0:

180 Moby Thesaurus words for "barbaric":
   Doric, Draconian, Gothic, Neanderthal, Philistine, Tartarean,
   aggressive, alien, animal, anthropophagous, atrocious, barbarian,
   barbarous, beastly, bestial, blatant, bloodthirsty, bloody,
   bloody-minded, bookless, brutal, brutalized, brute, brutish,
   cacophonous, cannibalistic, careless, clumsy, coarse, crude, cruel,
   cruel-hearted, deceived, demoniac, demoniacal, devilish, diabolic,
   doggerel, dysphemistic, erroneous, exotic, exterior, external,
   extraneous, extraterrestrial, extrinsic, faulty, fell, feral,
   ferine, ferocious, fiendish, fiendlike, fierce, flamboyant, flashy,
   florid, foreign, foreign-born, functionally illiterate, garish,
   gaudy, graceless, grammarless, gross, harsh, heathen, hellish,
   hoodwinked, ill-bred, ill-educated, illiterate, impolite,
   imprecise, improper, impure, in bad taste, incline, inconcinnate,
   inconcinnous, incorrect, indecorous, inelegant, infelicitous,
   infernal, inhuman, inhumane, intrusive, kill-crazy, led astray,
   loose, loud, low, lowbrow, malign, malignant, merciless,
   misinformed, misinstructed, mistaught, murderous, noncivilized,
   nonintellectual, ornate, ostentatious, outland, outlandish,
   outside, pagan, pitiless, primitive, raucous, rough,
   rough-and-ready, rude, ruthless, sadistic, sanguinary, sanguineous,
   satanic, savage, sharkish, showy, slavering, slipshod, slovenly,
   solecistic, strange, subhuman, tameless, tasteless, tawdry,
   troglodytic, truculent, ulterior, unbooked, unbookish,
   unbooklearned, unbriefed, unchristian, uncivil, uncivilized,
   uncombed, uncourtly, uncouth, uncultivated, uncultured,
   undignified, unearthly, unedified, uneducated, unerudite,
   uneuphonious, unfelicitous, ungentle, ungraceful, ungrammatic,
   unguided, unhuman, uninstructed, unintellectual, unkempt,
   unlearned, unlettered, unlicked, unliterary, unpolished, unread,
   unrefined, unscholarly, unschooled, unseemly, unstudious, untamed,
   untaught, untutored, vicious, vulgar, wild, wolfish