ἀποτειχιστέον
From LSJ
προγράψαντες οὖν τά τε θεωρήματα καὶ τὰ ἐπιτάγματα τὰ χρεῖαν ἔχοντα εἰς τὰς ἀποδείξιας αὐτῶν μετὰ ταῦτα γραψοῦμές τοι τὰ προκείμενα → having therefore written at the beginning the theorems and the postulates that are necessary for their proofs, we will then write out for you the propositions
English (LSJ)
A one must wall off: metaph., διαβολήν Them.Or.22.278a.
Greek (Liddell-Scott)
ἀποτειχιστέον: ῥηματ. ἐπίθ., πρέπει τις διὰ τειχῶν νὰ ἀποκλείσῃ, ἀποχωρίσῃ, νὰ ἐμποδίσῃ, μεταφ., διαβολὴν Θεμίστ. 278Α.
Spanish (DGE)
hay que separar por un muro fig. αὐτήν (διαβολήν) Them.Or.22.278a.