βρενθύομαι · brenthyomai — LSJ
bear oneself haughtily, hold oneʼs head high, swagger, ὑπὸ φρονήματος Ar. Pax 26, cf. Nu. 362, Pl. Smp. 221b, Luc. DMort. 20[10].8; πρός τινα Ar. Lys. 887; β. τι πρὸς αὑτόν Luc. Tim. 54; β. ἐπί τινι plume oneself on . . , Ath. 14.625b; ἐβρενθύετο Lib. Or. 56.17, Agath. 1.14; also, take umbrage, β. καὶ ἀγανακτῶν Ael. NA 5.36. (Either from βρένθος II or from βρένθειος, as Phld. Vit. p.37 J., Sch. Ar. Lys. 887.)