Filthy; dirty; foul; unclean, either literally or figuratively.
Of filthy habits.
Morally filthy; indecent; ribald; indelicate: applied to speech or behavior.
Nauseous; disgusting to taste or smell: as, a nasty medicine.
In a weakened sense, disagreeable; bad.
Foul; stormy; disagreeable; unpleasant: applied to the weather. Compare dirty and foul in the same sense.
Troublesome; annoying; difficult to deal with, or threatening trouble; of a kind to be avoided: as, a nasty customer to deal with; a nasty cut or fall.
Ill-natured; mean; dishonorable; hateful: as, a nasty remark; a nasty trick.
Synonyms 1 and 3. Nasty, Filthy, Foul, Dirty. These words are on the descending scale of strength. Nasty is the strongest word in the language for that which is offensive to sight, smell, or touch by the quality of its uncleanness or uncleanliness, The English fondness for the colloquial use of the word in connection with bad weather, and figuratively for anything disagreeable, is not matched by anything in America; on the contrary, the word is considered too strong for ordinary or delicate use, and foul is used of bad weather. All the words apply to that which is filled or covered in considerable degree with anything offensive. The moral uses of the word correspond with the physical.