The headword occurs at Hesiod,
Works and Days 410, in a gnomic utterance which later became proverbial: "not to put off to tomorrow and the day after" (see under
epsilon 1294, and cf.
epsilon 1295). It is preceded by a hiatus. The old termination in
-fi was probably originally adverbial, but is used indiscriminately, as here, in epic language from
Homer onward (see Chantraine,
Grammaire homérique 234ff.).
The Suda's gloss "
after the third [day]" is rather bizarre for "on the third day" (by Greek inclusive reckoning = our "on the second day").
Hesychius epsilon3025 correctly has "
to the third [day]",
ei)s tri/thn; likewise
Athenaeus,
Deipnosophists 3.100B [3.56 Kaibel] and a scholion to
Aristophanes,
Acharnians 172.