regaliter
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
Latin > French (Gaffiot 2016)
rēgālĭtĕr, royalement, en roi : Liv. 42, 51, 2 || en despote : Ov. M. 2, 397 || -lius J. Val. 1, 7.