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