undeadly · adjective, adverb1
- Old English · inherited fromundēadlīc“immortal, for all eternity”
- Middle English · inherited fromundedly
- English todayundeadly
From Middle English undedly, undeedly, undedlich, from Old English undēadlīc (“immortal, for all eternity”), equivalent to undead + -ly.
undeadly · adjective2
Etymology from Wiktionary, CC BY-SA 4.0.