ἐπιβομβέω
From LSJ
Τὸ νικᾶν αὐτὸν αὑτὸν πασῶν νικῶν πρώτη τε καὶ ἀρίστη. Τὸ δὲ ἡττᾶσθαι αὐτὸν ὑφ' ἑαυτοῦ πάντων αἴσχιστόν τε ἅμα καὶ κάκιστον. → Τo conquer yourself is the first and best victory of all, while to be conquered by yourself is of all the most shameful as well as evil
English (LSJ)
A make a booming noise with, τυμπάνῳ Luc.DDeor.12.1. 2. ring, οὔασι Nonn.D.40.503. II. trans., cause to sound, ἠχώ ib.21.230.