Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
* arrīsor (adr-), ōris, m. [arrideo], one who smiles on another, a flatterer, fawner: stultorum divitum arrosor, et (quod sequitur) adrisor, et, quod duobus his adjunctum est, derisor, Sen. Ep. 27.