2.Definition: disgustingly dirty; filled or smeared with offensive matter
"A nasty pigsty of a room"
3.Definition: exasperatingly difficult to handle or circumvent
"A nasty problem"
4.Definition: 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?"