Here's what rhymes with gradeable.
                        
                        
                    
                                gradable  degradable  persuadable  biodegradable  Words that almost rhyme with gradeable
capable  incapable  debatable  inflatable  inescapable  claimable  payable  traceable  saleable  salable  breakable  trainable  bailable  erasable  available  attainable  changeable  repayable  assailable  irreclaimable  reclaimable  resalable  occasional  obtainable  relational  insatiable  rotational  explainable  locational  unshakable  replaceable  unbreakable  unshakeable  unsaleable  untraceable  unsalable  conveyable  embraceable  occupational  operational  vocational  recreational  sustainable  unavailable  vibrational  unattainable  unchangeable  ascertainable  correlational  exchangeable  ideational  irreplaceable  unassailable  variational  maintainable  mutational  aberrational  mistakable  microwavable  probational  nonbreakable  educational  gravitational  sensational  situational  foundational  generational  gestational  subnational  unobtainable  avocational  computational  unmistakable  conversational  informational  interchangeable  motivational  observational  conformational  congregational  inspirational  navigational  translational  associational  unsustainable  coeducational  invitational  organizational  organisational  confrontational  nonoccupational  nonoperational  nonexchangeable  nonvocational  denominational  transformational  improvisational  noneducational  representational  intergenerational  noninterchangeable  nondenominational  interdenominational  nonrepresentational