The Collaborative International Dictionary of English v.0.48:

Rude \Rude\, a. [Compar. Ruder; superl. Rudest.] [F., fr. L.
   rudis.]
   1. Characterized by roughness; umpolished; raw; lacking
      delicacy or refinement; coarse.
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            Such gardening tools as art, yet rude, . . . had
            formed.                               --Milton.
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   2. Hence, specifically:
      (a) Unformed by taste or skill; not nicely finished; not
          smoothed or polished; -- said especially of material
          things; as, rude workmanship. "Rude was the cloth."
          --Chaucer.
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                Rude and unpolished stones.       --Bp.
                                                  Stillingfleet.
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                The heaven-born child
                All meanly wrapt in the rude manger lies.
                                                  --Milton.
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      (b) Of untaught manners; unpolished; of low rank; uncivil;
          clownish; ignorant; raw; unskillful; -- said of
          persons, or of conduct, skill, and the like. "Mine
          ancestors were rude." --Chaucer.
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                He was but rude in the profession of arms. --Sir
                                                  H. Wotton.
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                the rude forefathers of the hamlet sleep.
                                                  --Gray.
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      (c) Violent; tumultuous; boisterous; inclement; harsh;
          severe; -- said of the weather, of storms, and the
          like; as, the rude winter.
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                [Clouds] pushed with winds, rude in their shock.
                                                  --Milton.
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                The rude agitation [of water] breaks it into
                foam.                             --Boyle.
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      (d) Barbarous; fierce; bloody; impetuous; -- said of war,
          conflict, and the like; as, the rude shock of armies.
      (e) Not finished or complete; inelegant; lacking
          chasteness or elegance; not in good taste;
          unsatisfactory in mode of treatment; -- said of
          literature, language, style, and the like. "The rude
          Irish books." --Spenser.
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                Rude am I in my speech.           --Shak.
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                Unblemished by my rude translation. --Dryden.
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   Syn: Impertinent; rough; uneven; shapeless; unfashioned;
        rugged; artless; unpolished; uncouth; inelegant; rustic;
        coarse; vulgar; clownish; raw; unskillful; untaught;
        illiterate; ignorant; uncivil; impolite; saucy;
        impudent; insolent; surly; currish; churlish; brutal;
        uncivilized; barbarous; savage; violent; fierce;
        tumultuous; turbulent; impetuous; boisterous; harsh;
        inclement; severe. See Impertiment.
        [1913 Webster] -- Rude"ly, adv. -- Rude"ness, n.
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