late 12c., "supremely happy," also "consecrated, holy" (c. 1200), past-participle adjective from bless (v.). Reversed or ironic sense of "cursed, damned" is recorded from 1806. Related: Blessedly; blessedness.
our blessed land
the blessed assurance of a steady income
I'll be damned (or blessed or darned or goddamned) if I'll do any such thing
not a blessed dime
a blessed time