slaphappy

[ slap-hap-ee ]
/ ˈslæpˌhæp i /

adjective, slap·hap·pi·er, slap·hap·pi·est. Informal.

severely befuddled; punch-drunk: a slaphappy boxer.
agreeably giddy or foolish: After a martini he was slaphappy.
cheerfully irresponsible: a slaphappy crowd.

Origin of slaphappy

First recorded in 1935–40; slap1 + happy

British Dictionary definitions for slap-happy

slap-happy

adjective -happier or -happiest informal

cheerfully irresponsible or careless
dazed or giddy from or as if from repeated blows; punch-drunk