Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
Bibrax, actis (Bibe, Tab. Peuting.), f., a town in Gaul, in the territory of the Remi, now Bièvre, a small place between Laon and the river Aisne, Caes. B. G. 2, 6.