(ὑπεύθυνος; hypeúthynos) is used in the penal provisions of Greek decrees to mean ‘liable, owing’ (context: payment of monetary fines, e.g. IPArk 11,37), in Athens specifically for ‘accountable’. Every Athenian holding an office had to submit to an accountability process when his term had expired (εὔθυναι, eúthynai ) before the completion of which he could not leave the country or dispose of his assets. In the Egyptian papyri, hypeuthynos simply means ‘required to make payment’.
A. R. W. Harrison, The Law of Athens 2, 1971, 208-211