† ˈfluorous,a.Obs. [f. fluor + -ous.] Only in fluorous acid: (seequot. 1828: no such acid exists). 1790Kerr tr.Lavoisier's Elem.Chem. 185 (Table), Fluorous acid.a1828Lavoisier in Webster s.v., The fluorous acid is the acid of fluor in its first degree of oxygenation.