ἐπιμαρτύρησις
From LSJ
τραχὺς ἐντεῦθεν μελάμπυγός τε τοῖς ἐχθροῖς ἅπασιν → he is a tough black-arse towards his enemies, he is a veritable Heracles towards his enemies
English (LSJ)
εως, ἡ,
A confirmation, corroboration, Epicur.Sent.24, al.; -ήσεως δεῖσθαι M.Ant.7.62; ἡ ἐκ τῶν φαινομένων ἐ. S.E.P.1.181. II. Astrol., supporting by aspect, Paul.Al.O.4, Ptol.Tetr. 200.