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

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

Characterized by obscenity; indecent; indelicate; gross; filthy.

Vicious; offensively ill-tempered; insultingly mean; spiteful; as, a nasty disposition.

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

thoroughly unpleasant; "filthy (or foul or nasty or vile) weather we're having"

characterized by obscenity; "had a filthy mouth"; "foul language"; "smutty jokes"

disgustingly dirty; filled or smeared with offensive matter; "as filthy as a pigsty"; "a foul pond"; "a nasty pigsty of a room"