Blissful
来自Big Physics
Old English blīths, bliss, of Germanic origin; related to blithe.
wiktionary
From Middle English blisful, bislvol, equivalent to bliss + -ful.
etymonline
blissful (adj.)
late 12c., blisfulle, from bliss (n.) + -ful. Related: Blissfully; blissfulness.