Words That Rhyme With "Cosponsor" :
2 syllables:
ansar, answer, awner, Bonner, bonzer, bouncer, cancer, censer, censor, Chaucer, concert, conjure, conner, Connor, conster, crosser, dancer, denser, Donar, Doner, donner, dosser, fawner, fencer, fossor, goner, honor, honour, josser, lancer, launcher, mincer, monarch, monster, mosser, oncer, Oxnard, prancer, rondure, rosser, saucer, sensor, sponsor, Swaner, tensor, tonsure, tonsured, tosser, yawner, Zinsser
3 syllables:
advancer, announcer, condenser, dishonor, dishonour, embosser, enhancer, extensor, merganser, O'connor, responser, responsor, romancer