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