NASTY ( 'nas-te ) adj. 1. Twisted.2. Spitefully unfair.3. Causing dangerous and severe laughter. SYNONYMS: Hilarious. Deliciously fun. Sample usage: 'What a nasty, wicked book, filled with mayhem and mischief.' 'Only nasty criminals would kidnap a cuddly teddy bear!' 'Monsters attacking 'cause a kid picks his nose? That's nasty.' 'A witch on the Internet, a superhero who farts? All nasty too!'ANTONYMS: Nice.Boring.Plain old ordinary.