ритмичный

From LSJ

εἰς τὸν τετρημένον πίθον ἀντλεῖν → run water into a punctured pitcher, to the perforated jar bale water, labour in vain, labor in vain

Source

Russian > Greek

ἔνρυθμος, ἔρρυθμος, ῥυθμικός, ῥύθμιος