1. Cheerfully irresponsible
   - carefree, devil-may-care, freewheeling, happy-go-lucky, harum-scarum 
2. Dazed from or as if from repeated blows
   "slaphappy with exhaustion"
   - punch-drunk, silly

See also: confused, irresponsible

• Lanai Island
• lanate
• Lancashire
• Lancaster
• Lancastrian
• Lancastrian line
• lance
• lance corporal
• lance the boil
• lance-shaped
• lancelet
• lancelike
• Lancelot
• lanceolate
• lanceolate leaf
• lanceolate spleenwort
• lancer
• lancers
• lancet
• lancet arch
• lancet window
• lancet-shaped
• lancetfish
• lancewood
• lancewood tree