Here's what rhymes with filthify.
high thy vi hi shy sigh fi hy thigh vie psi hai cy fy sy thei phi by my why die lie y buy fly sky guy tie bi bye chi dye nigh pi pie spy thai verify dei fry ly quae rye sly ty wir awry lye mai muy nai wry falsify kai lai luy mei tai wai sty ossify stye slier apply dry supply try cry specify classify defy signify certify ply pacify pry ratify tri trie unify pri terrify untie crucify edify overlie ramify vilify aquae bonsai deify firefly spry vivify amebae calcify emulsify horrify turfy lanai overfly scarify scurfy versify shanghai vitrify overbuy reply thereby deny justify rely satisfy clarify hereby modify alkali simplify testify glorify gratify notify purify alibi alveoli fortify nullify rectify belie lullaby solidify typify amoebae codify dignify liquefy mollify resupply acidify mystify retry stratify stultify petrify reunify stupefy liquify declassify mummify prettify ripply speechify banzais yuppify identify imply nearby occupy stimuli whereby comply qualify butterfly goodbye intensify underlie amplify diversify magnify samurai beautify decry pupae descry mortify oversupply personify detoxify electrify triply ultrahigh blowfly misapply revivify barfly beatify drachmai refortify syllabify dandify solemnify multiply nuclei exemplify standby indemnify termini objectify demystify dragonfly reclassify dissatisfy hyperbolae gentrify quantify disqualify preoccupy cumuli misidentify oversimplify transmogrify