From Middle English aye, ai, aȝȝ, from Old Norse ei, ey, from Proto-Germanic *aiwa, *aiwō (compare Old English āwo, āwa, ā, ō, Middle Dutch ie, German je), from *aiwaz (compare Old English ǣ ("law"), West Frisian ieu ("century"), Dutch eeuw ("century")), from Proto-Indo-European *h₂eyu- ("long time") (compare Irish aois ("age, period"), Breton oad ("age, period"), Latin aevum ("eternity"), Ancient Greek αἰών). aevum.
"Appears suddenly about 1575, and is exceedingly common about 1600." Probably from use of aye as expression of agreement or affirmation, or from Middle English a ye ("oh yes"), or synthesis of both. More at oh, yea.
Probably of multiple motivations, the sounds having been chosen for functional reasons.
Modern English dictionary
Explore and search massive catalog of over 900,000 word meanings.
Word of the Day
Get a curated memorable word every day.
Challenge yourself
Level up your vocabulary by setting personal goals.