Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
fistŭlātor, ōris, m. [fistula], a player on the shepherd’s pipe, a piper: fistulatorem domi relinquetis, Cic. de Or. 3, 61, 227 (see the passage in connection); Cael. Aur. Tard. 5, 1, 22.