ἀρχισύμμαχος

From LSJ

νέῳ δὲ σιγᾶν μᾶλλον ἢ λαλεῖν πρέπει → it's fitting for a young man to keep silence rather than to speak (Menander)

Source

Spanish (DGE)

-ου, ὁ encargado de correos, jefe de mensajeros, PKlein Form.314.2 (V/VI d.C.), 271.3, PLaur.93.4 (ambos VI d.C.).