Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
2. lănĭo, ōnis, m. [1. lanio], a butcher (post-class.): lanionis instrumentum, Dig. 33, 7, 18; 1, 2, 2, § 24: quis tibi tunc, lanio, cernenti talia sensus, Sedul. Carm. 2, 127.