Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
aurōsus, a, um, adj. [aurum], of the color of gold, like gold (post-class.): pulvis, Pall. 1, 5, 1: harena, Lampr. Elag. 31 fin.: color, Veg. Art. Vet. 3, 17, 1.