Here's what rhymes with casterian.
carrion ovarian sectarian clarion agrarian librarian barbarian egalitarian vegetarian sanitarian vulgarian cnidarian authoritarian antiquarian libertarian veterinarian nonsectarian centenarian seminarian proletarian totalitarian trinitarian octogenarian nonagenarian sexagenarian humanitarian utilitarian communitarian disciplinarian parliamentarian latitudinarian septuagenarian valetudinarian Words that almost rhyme with casterian
barium chameleon honorarium vivarium aquarium sanitarium nobelium planetarium ferryman ferrymen lesbian thespian pedestrian vestrymen vestryman equestrian