ἀχάνεια
From LSJ
τί ἦ μοι ταῦτα περὶ δρῦν ἢ περὶ πέτρην → but what is this to me, about an oak or a rock | but what are these things about a tree or a rock to me | why all this about trees and rocks | why all this about what we have nothing to do with | but why am I off on this tangent
English (LSJ)
[χᾰ], ἡ, (ἀχᾰνής II)
A immensity, infinite expanse, τοῦ ὀπίσω καὶ πρόσω αἰῶνος M.Ant.12.7; infinite void, Syrian. in Metaph.60.5; εἰς ἀ. λήγειν Olymp. in Mete.82.22; ἡ τοῦ ἀπείρου ἀστάθμητος ἀ. Dam. Pr.53. 2 Medic., wide opening, cauity, Heliod.(?)ap.Orib.46.19.12, Paul.Aeg.6.107.
German (Pape)
[Seite 417] ἡ, unermeßliche Weite, Kluft, M. Anton. 12, 7 u. Medic.