ἀρχιληστής

From LSJ

ξένος ὢν ἀκολούθει τοῖς ἐπιχωρίοις νόμοις → as a foreigner, follow the laws of that country | when in Rome, do as the Romans do

Source

Greek (Liddell-Scott)

ἀρχιληστής: -οῦ, ὁ, ὁ ἀρχηγὸς λῃστρικῆς συμμορίας, Ἰωσήπ. Ἰουδ. Π. 1. 10, 5, κτλ.