toughie

Nouns

(n) an aggressive and violent young criminal hood, hoodlum, punk, strong-armer, thug, goon, tough,
(n) a particularly difficult or baffling question or problem stumper, poser, sticker,

Synonyms

hood hoodlum punk strong-armer thug goon tough stumper poser sticker

Words of close approximity

toughen toughly