Here's what rhymes with castume.
boom tomb doom whom room costume bloom womb broom loom plume zoom fume flume rheum assume gloom groom suum subsume abloom entomb foredoom resume consume perfume presume residuum exhume boxroom elbowroom legroom strongroom Words that almost rhyme with castume
tune spoon boon doin dune soon moon noon hewn shewn strewn foon coon prune swoon loon rune attune goon shoon afternoon balloon cartoon saloon opportune toluene baboon buffoon harpoon maroon typhoon bassoon tycoon croon festoon jejune lampoon spittoon immune lagoon platoon cocoon forenoon aucune pontoon raccoon dragoon impugn doubloon patroon bestrewn racoon macaroon honeymoon monsoon inopportune picayune poltroon dessertspoon tablespoon importune protozoon spermatozoon trinitrotoluene