[1] : The Collaborative International Dictionary of English v.0.48

ill-natured \ill`-na"tured\, a.
   1. of habitual bad temper; having an unpleasant disposition;
      surly; disagreeable; cross; peevish; fractious; crabbed;
      -- of people; as, an ill-natured person; an ill-natured
      disagreeable old man. opposite of good-natured.
      narrower terms: {argumentative, contentious,
      disputatious, disputative, litigious : {atrabilious,
      bilious, dyspeptic, liverish : {bristly, prickly,
      snappish, splenetic, waspish : {cantankerous, crotchety,
      ornery : {choleric, irascible, hotheaded, hot-headed,
      hot-tempered, quick-tempered, short-tempered : crabbed,
      crabby, cross, fussy, fussbudgety, grouchy, grumpy,
      bad-tempered, ill-tempered: {cranky, fractious,
      irritable, peevish, peckish, pettish, petulant, testy,
      tetchy, techy : crusty, curmudgeonly, gruff, ill-humored,
      ill-humoured: {dour, glowering, glum, moody, morose,
      saturnine, sour, sullen : {feisty, touchy : huffish,
      sulky: {misanthropic, misanthropical : {misogynous :
      shirty, snorty ill-tempered or annoyed: {shrewish,
      nagging, vixenish : {surly, ugly  also see: unpleasant.
      1913 webster + wordnet 1.5

   2. dictated by, or indicating, ill nature; spiteful. "the
      ill-natured task refuse." --addison.
      1913 webster

   3. intractable; not yielding to culture. r. "ill-natured
      land." --j. philips.

   3. not to one's liking; unpleasant; disagreeable. opposite of
      agreeable. wordnet sense 2 narrower terms: annoying,
      galling, chafing, irritating, nettlesome, pesky,
      pestiferous, pestilent, plaguy, plaguey, teasing,
      vexatious, vexing; {nerve-racking, nerve-wracking,
      stressful, trying 

   syn: disagreeable.
        wordnet 1.5 -- ill`-na"turedly, adv. --
        ill`-na"turedness, n.
        1913 webster
see also:
good-natured crabbed, crabby, cross, fussy, fussbudgety, grouchy, grumpy, bad-tempered, ill-tempered crusty, curmudgeonly, gruff, ill-humored, ill-humoured huffish, sulky shirty, snorty ill-tempered or annoyed unpleasant 
agreeable annoying, galling, chafing, irritating, nettlesome, pesky, pestiferous, pestilent, plaguy, plaguey, teasing, vexatious, vexing ill`-na"turedly ill`-na"turedness 

[2] : WordNet (r) 2.0

ill-natured
     adj : having an irritable and unpleasant disposition; "an
           ill-natured disagreeable old man" ant: good-natured
see also:
good-natured 

[3] : Moby Thesaurus II by Grady Ward, 1.0

21 moby thesaurus words for "ill-natured":
   bad-tempered, bitter, crabbed, cranky, cross, crusty, dour,
   evil-disposed, evil-tempered, gloomy, ill-affected,
   ill-conditioned, ill-disposed, ill-humored, ill-intentioned,
   ill-tempered, malevolent, morose, petulant, sour, sulky

Ill-Natured >> I Words
Ill-Natured, definition of term: Ill-Natured
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