[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

nastiest
     see nasty
see also:
nasty 

[3] : 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 

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