The story
- Old English · inherited fromhēlā
- Middle English · inherited fromhalou
- English todayhallo
From Middle English halou, halow, halloo (interjection used to call attention), representing Old English hēlā, ǣlā, ēalā (“O!, alas!, oh!, lo!”), equivalent to hey + lo.
Words from the same roots
Old Englishhēlā all →
heel
Etymology from Wiktionary, CC BY-SA 4.0.