Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
prŏhĭbĭtōrĭus, a, um, adj. [prohibitor], restraining, prohibitory (post-Aug.): avis, i. e. that restrains from an act by unfavorable omens, Plin. 10, 14, 17, § 37: interdictum, Dig. 43, 26, 1; Gai. Inst. 4, 140; Ambros. Par. 1, 5, 26.