The story
- Old English · inherited fromunmihtiġ“weak, not mighty”
- Middle English · inherited fromvnmyghty
- English todayunmighty
From Middle English vnmyghty, vnmyȝty, unmihti, from Old English unmihtiġ (“weak, not mighty”), equivalent to un- + mighty.
Etymology from Wiktionary, CC BY-SA 4.0.