ὀρθοέπεια
From LSJ
ἁρμονίη ἀφανὴς φανερῆς κρείττων → the hidden attunement is better than the obvious one, invisible connection is stronger than visible, harmony we can't see is stronger than harmony we can, unseen harmony is stronger than what we can see
English (LSJ)
ἡ,
A correctness of diction, Democr.20a, Pl.Phdr.267c, Phld.Rh.1.191 S., D.H.Dem.26, Quint.1.6.20.
German (Pape)
[Seite 374] ἡ, die grade, richtige Aussprache (recta locutio, Quint. 1, 6); Plat. Phaedr. 267 c; D. Hal. de vi Dem. 26. Diese grammatische Lehre behandelte Protagoras, Spengel artium scriptores p. 40 ff.
Greek (Liddell-Scott)
ὀρθοέπεια: ἡ, ὀρθότης ὕφους, λεκτικοῦ, Πλάτ. Φαῖδρ. 267C, πρβλ. Κοϊντιλ. 1. 6.