Here's what rhymes with operarium.
barium honorarium aquarium vivarium sanitarium planetarium Words that almost rhyme with operarium
carrion agrarian ovarian barbarian chameleon clarion librarian antiquarian libertarian vegetarian vulgarian nobelium authoritarian egalitarian proletarian sectarian veterinarian octogenarian centenarian sanitarian seminarian nonagenarian utilitarian trinitarian cnidarian humanitarian totalitarian latitudinarian nonsectarian sexagenarian communitarian disciplinarian parliamentarian septuagenarian valetudinarian biennium fermium millennium gentium requiem proscenium technetium quadrennium lutetium compendium endometrium lawrencium