The story
- Old English · inherited froma“on”
- Middle English · inherited froma-
- English todayadays
From Middle English a- + day + -s (“genitive ending”), from Old English a (“on”) + dæges (genitive of "day").
Words from the same roots
Middle Englisha- all →
a-ac-aslope
Etymology from Wiktionary, CC BY-SA 4.0.