Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
dēfrŭtum, i, n. (perh. for defervitum, sc. mustum), must boiled down (acc. to Varr. and Col., to one third; acc. to Plin., only to one half), Varr. ap. Non. 551, 24; Col. 12, 20 sq.; Plin. 14, 9, 11, § 80; Pall. Oct. 18; Plaut. Ps. 2, 4, 51; Verg. G. 4, 269.