physically filthy; disgustingly unclean

a nasty pigsty of a room.

offensive to taste or smell; nauseating.

offensive; objectionable

a nasty habit.

vicious, spiteful, or ugly

a nasty dog; a nasty rumor.

bad or hard to deal with, encounter, undergo, etc.; dangerous; serious

a nasty cut; a nasty accident.

very unpleasant or disagreeable

nasty weather.

morally filthy; obscene; indecent

a nasty word.

Slang . formidable

The young pitcher has a good fast ball and a nasty curve.

Informal . a nasty person or thing.

noun

despitefulness , ill will , malice , maliciousness , malignancy , malignity , meanness , poisonousness , spite , spitefulness , venomousness , viciousness