κουρεύομαι
From LSJ
αἰτῶ δ' ὑγίειαν πρῶτον, εἶτ' εὐπραξίαν, τρίτον δὲ χαίρειν, εἶτ' ὀφείλειν μηδενί → first health, good fortune next, and third rejoicing; last, to owe nought to any man
English (LSJ)
(κουρά) A take the tonsure, i.e. enter a monastery, of a nun, Just.Nov.134.10.1; have the hair cut, of four-year-old children, Sch.Nic.Al.417.