τεκμήρι-ον · tekmēri-on — LSJ
= τέκμαρ II (cf. Arist. Rh. 1357b8, 9), a sure sign or token, Hdt. 2.13, 9.100, etc.; τεκμηρίοισιν ἐξ οἰμωγμάτων A. Ag. 1366; καὶ μὴν στίβοι γε, δεύτερον τ. Id. Ch. 205; θανόντος πίστʼ ἔχων τ. S. El. 774; ἐμφανῆ τ. ib. 1109; ἀσφαλὲς τ. E. Rh. 94; ταῦτα δὴ πάντα τ. ὅτι . . Hp. VM 8: Medic., a sure symptom, Id. Prog. 25, Sor. 1.33, Gal. 18(2).306.
simply sign, symbol, τοῦ φιλαποδήμου Sor. Vit.Hippocr. 12.
proof (properly of an argumentative kind, opp. direct evidence, Is. 4.12, 8.6), A. Eu. 485, Pl. Tht. 158b, al.; opp. τὰ εἰκότα, Antipho 2.4.10; but οὐκ εἰκότα τ. Id. 4.4.2; τ. δίκαιον Id. 1.10; τ. τινός proof of a thing, A. Eu. 662, Ar. Av. 482, etc.; τ. δὲ τοῦδε τὸν Ὅμηρον λαβέ (i.e. the case of Homer) Philem. 97.5; also τ. περὶ τῶν μελλόντων And. 3.2, cf. Pl. Tht. 185b; τ. τινὸς δοῦναι, παρασχέσθαι, A. Pr. 826, X. Ages. 6.1; λέξω A. Eu. 447; δείξω, ἐπιδείξω, ἀποδεῖξαι, ib. 662, Supp. 53 (lyr.)
τεκμήριον δέ as an independent clause, now the proof of it is this (which follows), take this as a proof, Th. 2.39, D. 20.10, etc.; more fully, τ. δέ μοι τούτου τόδε· αἱ μὲν γὰρ φαίνονται κτλ. Hdt. 2.58; τ. δὲ τούτου καὶ τόδε· παρὰ μὲν Κύρου κτλ. X. An. 1.9.29; χρῆσθαι τεκμηρίῳ ὅτι . . (ὅτι introducing the reason, not the fact) And. 1.24, cf. Lys. 30.15.
in the Logic of Aristotle, demonstrative proof, opp. to the fallible σημεῖον and εἰκός, APr. 70b2, Rh. 1357b4, 1402b19, cf. Phld. Rh. 1.369 S.