1. An aggressive and violent young criminal
   - hood, hoodlum, goon, punk, thug, tough, strong-armer 
2. A particularly difficult or baffling question or problem
   - poser, stumper, sticker

Derived forms: toughies

Type of: criminal, crook, felon, malefactor, outlaw, problem

• copestone
• copier
• copilot
• coping
• coping saw
• coping stone
• copious
• copiously
• copiousness
• coplanar
• Copland
• Copley
• copolymer
• copolymerise
• copolymerize
• copper
• copper beech
• copper color
• copper colored
• copper colour
• copper coloured
• copper glance
• copper mine
• copper nose
• copper oxide