προθνήσκειν
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
Greek > English (Woodhouse Verbs Reversed)
(see also: προθνήσκω) be a martyr to, die for
Lexicon Thucydideum
prius mori, to die first, 2.52.4.