Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
strīdŭlus, a, um, adj. [strideo], creaking, rattling, hissing, whizzing, buzzing, stridulous (poet. and in post-Aug. prose): stridula cornus (i. e. hasta), Verg. A. 12, 267: fraxinus, Claud. in Ruf. 3, 218: plaustra, Ov. Tr. 3, 12, 30: fax lacrimoso stridula fumo fuit, id. M. 10, 6: manus monstri (i. e. elephanti), Sil. 9, 627: stridula et tenuis vox, Sen. Ep. 56, 2: examina apum, Claud. Cons. Hon. 4, 380.