Lewis & Short

Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.

Allō̆brox, ăgis, and plur. Allō̆brŏ-ges, um, m. (acc. sing. Allobroga, Juv. 7, 214), the Allobroges, in Ptol. Ἀλλόβρυγες, a warlike people in Gallia Narbonensis, on the east side of the Rhone, and to the north of l’Isère, now Savoy, Dép. de l’Isère, and a part of the Dép. de l’Ain, Caes. B. G. 1, 6 al.; Cic. Div. 1, 12, 21; Liv. 21, 31; Flor. 3, 2; cf. Mann. Gall. 57 and 91.
The sing. is found only in the poets, Hor. Epod. 16, 6: qui totiens Ciceronem Allobroga (i. e. barbare loquentem) dixit, Juv. 7, 214.
Hence, deriv. adj.: Allō̆brŏgĭcus, a, um, Allobrogian: vinum, Cels. 4, 5: vitis, Plin. 14, 2, 4, § 3 al.
Hence, a surname of Q. Fabius Maximus, as conqueror of the Allobroges, Vell. 2, 10.