Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
† cērȳcĭum or cērȳcēum, ii, n., = κηρύκιον or κηρύκειον, a pure Greek form for caduceus, the herald’s staff, Dig. 1, 8, 8; Mart. Cap. 4, § 331.