Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
mellĭfĭcĭum, ii, n. [mel-facio], the making of honey: ad mellificium aptissimum est thymum, Varr. R. R. 3, 16, 4; Col. 9, 13, 13.
mellĭfĭcus, a, um, adj. [mel-facio], honey-making, fit for making honey (postAug.): opus, Col. 9, 13, 14: saltus, id. 9, 8, 8; v. mellifex.