ἔον

ἔον, Ep. (Il. 23.643) and Aeol. for ἦν, 1 sg. impf. of εἰμί (q.v.):— but ἐόν, Ion. for ὄν, part. neut. of εἰμί.
Liddell, Scott & Jones
A Greek-English Lexicon, 1940
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