- happy-go-lucky (adv.)
[happy-go-lucky 词源字典]
- also happy go lucky, 1670s, "haphazard, in any way one pleases; every man for himself." Earlier as happy-be-lucky (1630s). The adjective, of persons, recorded from 1835, "careless," hence "carefree."[happy-go-lucky etymology, happy-go-lucky origin, 英语词源]