ὀξυντέον
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)
A one must pronounce with the acute accent, Sch.Il.15.445.
Greek (Liddell-Scott)
ὀξυντέον: ῥηματ. ἐπίθετ. τοῦ ὀξύνω, δεῖ ὀξύνειν, δηλ. ὀξυτονεῖν, Σχόλ. Ἑνετ. εἰς Ἰλ. Ο. 445· ― ὀξυτονητέον, Σχόλ. εἰς Ἀπολλ. Ρόδ. Α΄, 132.