ὀρθόκωλος
From LSJ
ἀμήχανον δὲ παντὸς ἀνδρὸς ἐκμαθεῖν ψυχήν τε καὶ φρόνημα καὶ γνώμην, πρὶν ἂν ἀρχαῖς τε καὶ νόμοισιν ἐντριβὴς φανῇ → hard it is to learn the mind of any mortal or the heart, 'till he be tried in chief authority | it is impossible to know fully any man's character, will, or judgment, until he has been proved by the test of rule and law-giving
English (LSJ)
ον,
A with limbs fixed in extended position, ib.623 ; ἵπποι τὰ γόνατα ἔχοντες σκληρὰ καὶ ὅμοια τοῖς ὀρθοκοίλοις (sic) Hippiatr.115.
