slap-happy
adjective /ˌslæp ˈhæpi/
  /ˌslæp ˈhæpi/
(informal)- cheerful, but careless about things that should be taken seriously嘻嘻哈哈的;什么都不放在心上的;大大咧咧的 - a slap-happy approach to life大大咧咧的生活态度 
 
- a slap-happy approach to life
- (especially North American English) (also punch-drunk British and North American English)(of a boxer拳击手 拍打开心: 由于多次被头部击中而感到困惑
- (especially North American English) (also punch-drunk British and North American English)unable to think clearly; in a confused state思维混乱的;糊涂的