Lewis & Short

Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.

cătōnĭum, ii, n. [κάτω], the Lower World, Laber. ap. Gell. 16, 7, 4; cf. Schol. Juv. p. 65 Cram.
Hence the play upon the word: vereor, ne in catonium Catoninos, Cic. Fam. 7, 25, 1 B. and K. (others read catomum; v. this word).