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

nasty \nas"ty\ n.as"ty^, a. compar. nastier
   n.as"ti^~er; superl. nastiest. for older nasky;
   cf. dial. sw. naskug, nasket.
   1. offensively filthy; very dirty, foul, or defiled;
      disgusting; nauseous.
      1913 webster

   2. hence, loosely: offensive; disagreeable; unpropitious;
      wet; drizzling; as, a nasty rain, day, sky.
      1913 webster

   3. characterized by obscenity; indecent; indelicate; gross;
      filthy.
      1913 webster

   4. vicious; offensively ill-tempered; insultingly mean;
      spiteful; as, a nasty disposition.
      pjc

   5. difficult to deal with; troublesome; as, he fell of his
      bike and got a nasty bruise on his knee. slang
      pjc

   syn: nasty, filthy, foul, dirty.

   usage: anything nasty is usually wet or damp as well as
          filthy or dirty, and disgusts by its stickiness or
          odor; but filthy and foul imply that a thing is filled
          or covered with offensive matter, while dirty
          describes it as defiled or sullied with dirt of any
          kind; as, filthy clothing, foul vapors, etc.
          1913 webster
see also:
nastier nastiest nasty filthy foul dirty 

[2] : WordNet (r) 2.0

nasty
     adj 1: offensive or even of persons malicious; "in a nasty mood";
            "a nasty accident"; "a nasty shock"; "a nasty smell";
            "a nasty trick to pull"; "will he say nasty things at
            my funeral?"- ezra pound syn: awful ant: nice
     2: exasperatingly difficult to handle or circumvent; "a nasty
        problem"; "a good man to have on your side in a tight
        situation" syn: tight
     3: thoroughly unpleasant; "filthy or foul or nasty or vile
        weather we're having" syn: filthy, foul, vile
     4: characterized by obscenity; "had a filthy mouth"; "foul
        language"; "smutty jokes" syn: filthy, foul, smutty
     5: disgustingly dirty; filled or smeared with offensive matter;
        "as filthy as a pigsty"; "a foul pond"; "a nasty pigsty of
        a room" syn: filthy, foul
     also: nastiest, nastier
see also:
awful nice tight filthy foul vile 
smutty nastiest nastier 

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

227 moby thesaurus words for "nasty":
   fescennine, rabelaisian, abhorrent, abominable, abusive, acute,
   annoying, arrant, atrocious, awful, awkward, bad, bad-tempered,
   baleful, barfy, base, bawdy, beastly, below contempt,
   beneath contempt, bitchy, black, blameworthy, blue, boorish,
   brackish, brutal, caddish, cantankerous, churlish, cloying, coarse,
   contemptible, crabbed, cranky, crappy, critical, crotchety, crude,
   cruel, cussed, dangerous, deplorable, despicable, detestable,
   difficult, dire, dirty, disagreeable, disgusting, dreadful,
   egregious, enormous, evil, execrable, fecal, feculent, fetid,
   filthy, flagrant, flyblown, forbidding, foul, foul-mouthed,
   foul-spoken, foul-tongued, fulsome, gloppy, grievous, gross,
   grubby, gunky, harmful, hateful, heinous, high, horrible, horrid,
   icky, ignoble, ill-bred, ill-natured, ill-tempered, improper,
   impure, inconsiderate, indecent, indecorous, indelicate, infamous,
   iniquitous, insensitive, invidious, irascible, ithyphallic,
   lamentable, lewd, licentious, loathsome, lousy, loutish, louty,
   lurid, maggoty, malefic, maleficent, malevolent, malicious, malign,
   malignant, malodorous, mawkish, mean, mephitic, miasmal, miasmic,
   monstrous, mucky, nauseant, nauseating, nauseous, nefarious,
   noisome, notorious, noxious, objectionable, obnoxious, obscene,
   odious, off color, offensive, ordurous, ornery, outrageous,
   overripe, painful, pitiable, pitiful, poisonous, pornographic,
   puky, putrid, rancid, rank, raunchy, rebarbative, regrettable,
   repellent, reprehensible, repugnant, repulsive, revolting, ribald,
   risque, rotten, rude, sad, salacious, scabby, scandalous,
   scatological, schlock, scummy, scurfy, scurrile, scurrilous,
   scurvy, serious, severe, shabby, shameful, shitty, shocking,
   shoddy, sickening, slabby, slimy, sloppy, sloshy, sludgy, slushy,
   smoking-room, smutty, soily, sordid, spiteful, spoiled, sposhy,
   squalid, stinking, suggestive, sultry, surly, tactless, terrible,
   too bad, ugly, unchaste, unclean, uncleanly, unfeminine, ungenteel,
   ungentle, ungentlemanly, unladylike, unpleasant, unprintable,
   unrefined, unrepeatable, unsavory, unseemly, unsolicitous,
   untoward, vicious, vile, villainous, vomity, vulgar, weevily,
   wicked, woeful, wormy, worst, worthless, wretched, yecchy, yucky

Nasty >> N Words
Nasty, definition of term: Nasty
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