The Collaborative International Dictionary of English v.0.48:

Uncivilized \Un*civ"i*lized\, a.
   1. Not civilized; not reclaimed from savage life; rude;
      barbarous; savage; as, the uncivilized inhabitants of
      Central Africa.
      [1913 Webster]

   2. Not civil; coarse; clownish. [R.] --Addison.
      [1913 Webster]

WordNet (r) 3.0 (2006):

uncivilized
    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]

Moby Thesaurus II by Grady Ward, 1.0:

103 Moby Thesaurus words for "uncivilized":
   Draconian, Gothic, Neanderthal, Tartarean, animal, anthropophagous,
   atrocious, barbarian, barbaric, barbarous, beastly, bestial,
   bloodthirsty, bloody, bloody-minded, boorish, brutal, brutalized,
   brute, brutish, cannibalistic, churlish, cloddish, coarse, crude,
   cruel, cruel-hearted, demoniac, demoniacal, devilish, diabolic,
   fell, feral, ferine, ferocious, fiendish, fiendlike, fierce,
   gauche, gross, hellish, ill-bred, ill-mannered, impolite,
   incondite, inelegant, infernal, inhuman, inhumane, kill-crazy,
   loutish, lowbred, malign, malignant, merciless, murderous,
   noncivilized, outlandish, philistine, pitiless, primitive,
   provincial, rough, rough-and-ready, rude, rugged, ruthless,
   sadistic, sanguinary, sanguineous, satanic, savage, sharkish,
   slavering, subhuman, tameless, troglodytic, truculent, unchristian,
   uncivil, uncombed, unconscionable, uncouth, uncultivated,
   uncultured, uneducated, ungentle, ungodly, unholy, unhuman,
   unkempt, unlearned, unlicked, unmannerly, unpolished, unrefined,
   unsophisticated, untamed, untutored, vicious, wicked, wild,
   wolfish