δυσμαθῶς

From LSJ

πέτρην κοιλαίνει ρανὶς ὕδατος ἐνδελεχείῃ → constant dropping wears away a stone, constant dripping will wear away the hardest stone, little strokes fell big oaks, constant dripping wears the stone, constant dropping wears the stone, constant dripping will wear away a stone

Source

Spanish

con torpeza

Russian (Dvoretsky)

δυσμᾰθῶς: непонятливо, плохо усваивая (ὥσπερ ἀπονεναρκωμένα ἤθη Plat.).