Lewis & Short

Argentŏrātus, i, f., the name of a city, now Strasburg in Alsace, Amm. 15, 11; cf. Mann. Gall. 270.
Hence, Argen-tŏrātensis, e, adj., of or pertaining to Argentoratus: campi, Aur. Vict. Ep. 42: pugna, Amm. 17, 1.