Greek word
epioúsios
ἐπιούσιος
What it means
tomorrows
tomorrow's; but more probably from epí (ἐπί) and a derivative of the present participle feminine of eimí (εἰμί); for subsistence, i.e. needful
Where it comes from
perhaps from the same as epioûsa (ἐπιοῦσα)