Here's what rhymes with additam.
                        
                        
                    
                                teatime  arboretum  Words that almost rhyme with additam
beaten  didn  deepen  cheapen  phaeton  wheaten  unbeaten  neaten  region  freedom  legion  needn  sweeten  cretin  steepen  collegian  overeaten  diesem  rerum  cerium  chiefdom  labium  threesome  fiefdom  sheikdom  sheikhdom  hominum  capsicum  cilium  samarium  francium  museum  mausoleum  imperium  encomium  trapezium  solarium  coliseum  protactinium