μονογαμέω
From LSJ
ἐν μὲν γὰρ ταῖς ἐπιστολαῖς αὐτοῦ οὐδὲ μνήμην τῆς οἰκείας προσηγορίας ποιεῖται, ἢ πρεσβύτερον ἑαυτὸν ὀνομάζει, οὐδαμοῦ δὲ ἀπόστολον οὐδ' εὐαγγελιστήν (Eusebius, Demonstratio evangelica 3.5.88) → For in his epistles he doesn't even make mention of his own name — or simply calls himself the elder, but nowhere apostle or evangelist.
English (LSJ)
A to be the husband of one wife, Cat.Cod.Astr.2.209.