Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
2. luxus, ūs, m. [1. luxus], a dislocation (ante- and post-class.): ad luxum aut fracturam alliga: sanum fiet, Cato, R. R. 160; App. Flor. p. 354 med.; Plin. Val. 2, 49.