nasty

adj. smelly; evil; severe; disgusting; dangerous; unpleasant; obscene

Nasty could mean any of these:-A word to describe something bad or disgusting"Nasty (song)": a song by Janet JacksonNasty, Hertfordshire, a village in Hertfordshire, EnglandNasty (cat), Books on Tape's cat.
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Adjective
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
(synonym) awful
(antonym) nice
(similar) dirty, filthy, lousy
(see-also) unpleasant
(attribute) nastiness
2. exasperatingly difficult to handle or circumvent; "a nasty problem"; "a good man to have on your side in a tight situation"
(synonym) tight
(similar) difficult, hard
3. thoroughly unpleasant; "filthy (or foul or nasty or vile) weather we're having"
(synonym) filthy, foul, vile
(similar) inclement
(classification) colloquialism
4. characterized by obscenity; "had a filthy mouth"; "foul language"; "smutty jokes"
(synonym) filthy, foul, smutty
(similar) dirty
5. disgustingly dirty; filled or smeared with offensive matter; "as filthy as a pigsty"; "a foul pond"; "a nasty pigsty of a room"
(synonym) filthy, foul
(similar) dirty, soiled, unclean

(superl.)
Offensively filthy; very dirty, foul, or defiled; disgusting; nauseous.
  

(superl.)
Hence, loosely: Offensive; disagreeable; unpropitious; wet; drizzling; as, a nasty rain, day, sky.
  

(superl.)
Characterized by obcenity; indecent; indelicate; gross; filthy.
  

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