Word Origin & History. happy mid-14c., lucky, from hap chance, fortune (see haphazard), sense of very glad first recorded late 14c. Ousted O.E. eadig (from ead wealth, riches) and gesÃ¦lig, which has become silly. O.E. bliÃ°e happy survives as blithe. From Greek to Irish, a great majority of the European words for happy at first meant lucky.. An exception is Welsh, where the word used first meant wise..