Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
fundĭtor, ōris, m. [funda], one who fights with a sling, a slinger, σφενδονίτης, a sort of light-armed soldier (cf.: jaculator, sagittarius), Caes. B. G. 2, 7, 1; 2, 10, 1; 2, 19, 4; 2, 24, 4 et saep.; Sall. J. 46, 7; 49, 6 al.