Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
‡ sŭperlīmen, ĭnis, n. [super-limen], a lintel, Plin. 29, 4, 26, § 83: LAPIDEVM, Inscr. Marin. Fratr. Arv. p. 324.