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