Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
rūfo, āre, v. a. [rufus], to make or color reddish: capillum, Plin. 15, 22, 24, § 87; 23, 2, 32, § 67; 23, 4, 46, § 91.