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