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