δεικτέον
γεγόναμεν γὰρ πρὸς συνεργίαν ὡς πόδες, ὡς χεῖρες, ὡς βλέφαρα, ὡς οἱ στοῖχοι τῶν ἄνω καὶ κάτω ὀδόντων. τὸ οὖν ἀντιπράσσειν ἀλλήλοις παρὰ φύσιν → we are all made for mutual assistance, as the feet, the hands, and the eyelids, as the rows of the upper and under teeth, from whence it follows that clashing and opposition is perfectly unnatural
English (LSJ)
one must show, prove, X.Mem.3.5.8; περίτινος Theophrastus CP3.7.5; τοὺς νόμους δεικτέον μοι it is my duty to point out.., D.18.58, cf. Porph.Abst.3.7.
Spanish (DGE)
1 hay que mostrar τοὺς νόμους D.18.58, τοῦτ' αὖ δ. ... προσῆκον αὐτοῖς X.Mem.3.5.8
•hay que demostrar c. part. pred., Plb.12.8.1, ὅτι Luc.Par.13, Euc.10.17.
2 hay que explicar o dar una explicación οὐκ ἐγχωρεῖ λαβεῖν ὅρους, ἐκ δὲ τοῦ ἀδιορίστου δ. Arist.APr.27b20, ὑπὲρ ἧς Thphr.CP 3.7.5, περὶ τοῦ ἑξῆς Aristox.Harm.66.1, περὶ ὧν Lyd.Mag.1.46.
3 hay que servir de guía Plot.1.3.3.
Dutch (Woordenboekgrieks.nl)
δεικτέον, adj. verb. van δείκνυμι er moet bewezen worden.