Ay
来自Big Physics
late 16th century: probably from I, first person personal pronoun, expressing assent.
wiktionary
ay
From Middle English ai, from Old Norse ei, from Proto-Germanic *aiwaz(“eternity, age”), from Proto-Indo-European *h₂eyu-(“vitality”); cognate with Old English ā, Ancient Greek ἀεί(aeí, “always”), and Latin aevum(“an age”).
ay
etymonline
ay (interj.)
see aye.
