The Collaborative International Dictionary of English v.0.48:

Uncouth \Un*couth"\ ([u^]n*k[=oo]th"), a. [OE. uncouth, AS.
   unc[=u][eth] unknown, strange: un- (see Un- not) +
   c[=u][eth] known, p. p. of cunnan to know. See Can to be
   able, and cf. Unco, Unked.]
   1. Unknown. [Obs.] "This uncouth errand." --Milton.
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            To leave the good that I had in hand,
            In hope of better that was uncouth.   --Spenser.
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   2. Uncommon; rare; exquisite; elegant. [Obs.]
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            Harness . . . so uncouth and so rich. --Chaucer.
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   3. Unfamiliar; strange; hence, mysterious; dreadful; also,
      odd; awkward; boorish; as, uncouth manners. "Uncouth in
      guise and gesture." --I. Taylor.
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            I am surprised with an uncouth fear.  --Shak.
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            Thus sang the uncouth swain.          --Milton.
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   Syn: See Awkward.
        [1913 Webster] -- Un*couth"ly, adv. --
        Un*couth"ness, n.
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Moby Thesaurus II by Grady Ward, 1.0:

138 Moby Thesaurus words for "uncouth":
   Doric, Gothic, Neanderthal, abandoned, all thumbs, animal, awkward,
   barbarian, barbaric, barbarous, bestial, bizarre, blunderheaded,
   blundering, boorish, broad, brutal, brutish, bumbling, bungling,
   butterfingered, cacophonous, careless, churlish, cloddish,
   clodhopping, clownish, clumsy, clumsy-fisted, coarse, countrified,
   country-born, country-bred, crass, crude, cumbersome, curious,
   deserted, desolate, discourteous, disrespectful, doggerel,
   dysphemistic, earthy, eccentric, erratic, farmerish,
   fingers all thumbs, forsaken, frank, from the sticks, fumbling,
   gauche, gawkish, gawky, graceless, gross, gutter, ham-fisted,
   ham-handed, harsh, hayseed, heavy-handed, hick, hicky, hobnailed,
   hulking, hulky, ill-bred, ill-mannered, impermanent, impolite,
   improper, impure, in bad taste, inconcinnate, inconcinnous,
   incorrect, indecorous, inelegant, infelicitous, inurbane,
   left-hand, left-handed, loutish, low, lubberly, lumbering, lumpen,
   lumpish, maladroit, noncivilized, oafish, odd, oddball, outlandish,
   ponderous, primitive, quaint, queer, rank, raw, rough,
   rough-and-ready, rube, rude, rummy, savage, sloppy, solitary,
   stiff, tasteless, troglodytic, uncalled-for, uncivil, uncivilized,
   uncombed, uncourtly, uncultivated, uncultured, undignified,
   uneuphonious, unfelicitous, ungainly, ungraceful, unhandy, unkempt,
   unlicked, unpolished, unrefined, unseemly, untamed, unwieldy,
   up-country, vulgar, wild, yokel, yokelish