Here's what rhymes with cautionary.
marry merry nary very vary coronary fairy bury dairy ferry wary cherry hairy berry sherry tarry canary parry unwary harry tare barre terry faerie wherry ordinary customary missionary commentary urinary prairie visionary corollary honorary mercenary seminary commissary scary ternary remarry apiary cassowary humeri nondairy necessary secondary monetary pulmonary capillary dictionary dietary solitary stationary adversary cemetery momentary sanitary ancillary dysentery estuary sedentary veterinary apothecary emissary funerary sanguinary stationery centenary luminary aviary bacillary buffoonery legionary pessary equerry sectary military literary secretary temporary arbitrary hereditary imaginary monastery sanctuary legendary reactionary unitary budgetary salutary culinary fiduciary functionary itinerary mortuary papillary savagery statuary diversionary actuary concessionary dromedary huckleberry lapidary recessionary bilberry elderberry topiary chokecherry plagiary uncustomary unnecessary evolutionary subsidiary disciplinary fragmentary involuntary maxillary pituitary discretionary inflationary planetary exclusionary obituary confectionery deflationary dignitary epistolary expansionary probationary supernumerary unsanitary beriberi breviary insanitary voluptuary elocutionary nonliterary tercentenary contemporary extraordinary revolutionary preliminary vocabulary judiciary pecuniary tributary expeditionary genitourinary tutelary nonmilitary eleemosynary geostationary bicentenary nonhereditary beneficiary proprietary paramilitary constabulary noninflationary cardiopulmonary interplanetary undersecretary interdisciplinary multidisciplinary counterrevolutionary Words that almost rhyme with cautionary
belly allele jelly smelly deli telly vermicelli underbelly many messy heavy ready fairly rarely barely semi petty levy penny antennae heady levee medley unfairly jetty teddy bevy faery jenny kepi leggy recce sedgy veggie healthy steady wealthy deadly lengthy gentry unhealthy fleshy squarely carefree sentry sexy sketchy spaghetti sweaty unsteady vestry belfry deathly gayety hefty machete sullenly confetti fidgety pebbly tempi testy breathy dressy pesky thready lefty wetly already especially twenty assembly scarcely elementary gently plenty freshly immensely densely frenzy deftly coquetry fleshly halfpenny stealthy hostelry tensely trendy aplenty libretti maidenly marquetry adeptly effendi ineptly directly friendly correctly complementary intensely epilepsy intently unfriendly sacredly baronetcy preciously woodenly indirectly expressly incorrectly apoplexy excellency complexly narcolepsy catalepsy cognoscenti deviancy reassembly confusedly equivalently grotesquely circumspectly penitently ambivalently