Here's what rhymes with rectangularity.
rarity angularity clarity parity celerity verity popularity polarity regularity singularity temerity granularity hilarity capillarity prosperity similarity solidarity posterity irregularity familiarity sincerity disparity peculiarity bipolarity dexterity insincerity unfamiliarity subsidiarity Words that almost rhyme with rectangularity
therapy parody fidelity melody chemotherapy psychotherapy radiotherapy hydrotherapy hypnotherapy physiotherapy readily legacy heresy brevity leprosy merrily warily wearily amenity acerbity retinae apparently carefully necessity density heavily penalty seventy deputy allegedly heredity terribly serenity severally solemnity verily militarily sesame revelry telemetry telepathy velvety legibly prayerfully identity necessarily primarily chemistry destiny integrity presently specially steadily extremity heavenly jealousy mentally ordinarily supremacy centrally chemically peasantry pleasantly specialty carelessly felony longevity pedigree perplexity tenancy clemency dreadfully immensity medically recklessly weaponry heraldry inequity pedantry pleasantry unbearably credibly nonentity tenantry testily blessedly devilry fretfully negligee essentially intensity tendency complexity potentially pregnancy secondly temporarily voluntarily arbitrarily hegemony momentarily ascendancy customarily indemnity sensibly ascendency convexity dentistry jealously restlessly breathlessly flexibly incrementally lamentably professedly regretfully unpleasantly helpfully regrettably unsteadily vasectomy successfully accidentally ostensibly transparency helplessly incessantly incredibly tremendously unnecessarily marvellously relentlessly secondarily sequentially splendidly acceptably clandestinely confessedly mastectomy transparently impeccably inclemency resentfully tangentially temperamentally tonsillectomy dependency fundamentally discrepancy extraordinarily respectfully unsuccessfully biochemistry contentedly developmentally insensibly preferentially confidentially indelibly inexpressibly providentially biochemically geochemistry impetuously instrumentally respectably expectancy experimentally incidentally conscientiously environmentally exponentially hysterectomy expectantly existentially incontestably quintessentially sentimentally unacceptably independently contemptuously coincidentally indispensably superintendency