Here's what rhymes with decumulation.
                        
                        
                    
                                relation  nation  accumulation  emulation  oration  ablation  aeration  elation  granulation  creation  duration  location  regulation  station  correlation  elevation  isolation  migration  revelation  rotation  salvation  violation  allocation  irrigation  simulation  annihilation  insulation  modulation  mutation  narration  negation  oscillation  allegation  appellation  inhalation  ovulation  sedation  summation  ulceration  adulation  coloration  dilation  information  education  operation  population  application  formation  circulation  integration  legislation  occupation  radiation  reputation  translation  variation  calculation  formulation  illustration  immigration  indication  inflation  innovation  liberation  motivation  obligation  realization  stimulation  taxation  agitation  alienation  alteration  celebration  delegation  frustration  illumination  imitation  implication  inclination  inflammation  installation  irritation  medication  meditation  navigation  nomination  notation  plantation  recreation  reservation  utilization  vacation  valuation  ventilation  vibration  accusation  affiliation  affirmation  aggregation  animation  approbation  aviation  calibration  causation  cessation  coagulation  compilation  consolation  derivation  desolation  dilatation  emigration  filtration  litigation  maturation  mediation  moderation  ordination  probation  realisation  reformation  replication  retardation  starvation  toleration  unification  validation  vocation  aberration  adoration  alternation  amputation  automation  cancellation  castration  citation  coronation  damnation  deregulation  donation  duplication  escalation  hydration  imputation  inoculation  intimation  intonation  invocation  iteration  recitation  reclamation  relocation  renovation  reparation  revocation  usurpation  situation  combination  communication  generation  association  conversation  corporation  foundation  imagination  observation  preparation  publication  separation  activation  adaptation  admiration  appreciation  conservation  cultivation  declaration  deviation  inspiration  invitation  limitation  preservation  restoration  sensation  arbitration  aspiration  assimilation  collaboration  computation  confirmation  congregation  consultation  decoration  degradation  dissertation  domination  elimination  estimation  fixation  hesitation  initiation  manipulation  oxidation  penetration  proclamation  propagation  quotation  relaxation  resignation  respiration  saturation  segregation  speculation  temptation  termination  vegetation  annexation  articulation  attenuation  authorization  complication  dedication  deprivation  distillation  elaboration  fascination  federation  graduation  habitation  humiliation  importation  incarnation  incubation  infiltration  ionization  irradiation  localization  mobilization  polarization  remuneration  retaliation  veneration  abbreviation  amalgamation  bifurcation  capitulation  conflagration  conformation  connotation  consecration  constellation  consummation  culmination  demarcation  deputation  divination  elongation  elucidation  enumeration  eradication  fibrillation  fluctuation  germination  gestation  immunization  implantation  inauguration  innervation  interpolation  interrogation  masturbation  normalization  perforation  perturbation  prolongation  provocation  refutation  sanitation  stagnation  stipulation  utilisation  vindication  visitation  organization  concentration  examination  explanation  civilization  classification  cooperation  evaluation  presentation  transformation  compensation  discrimination  exploration  modification  organisation  orientation  transportation  acceleration  accommodation  anticipation  appropriation  condemnation  confrontation  consolidation  contemplation  coordination  deformation  designation  destination  documentation  emancipation  excitation  incorporation  indignation  negotiation  proliferation  regeneration  registration  amplification  assassination  civilisation  clarification  colonization  condensation  deliberation  denomination  desperation  dislocation  dissipation  evacuation  evaporation  excavation  expiration  fabrication  fermentation  generalization  globalization  gratification  liberalization  modernization  multiplication  notification  preoccupation  ratification  socialization  verification  adjudication  affectation  augmentation  authentication  calcification  centralization  commendation  conciliation  confiscation  consternation  constipation  crystallization  dehydration  delineation  deportation  devastation  exaltation  exclamation  exhortation  fertilization  gravitation  liquidation  menstruation  mortification  perspiration  polymerization  punctuation  refrigeration  regurgitation  renunciation  repudiation  resuscitation  sterilization  subjugation  urbanization  vaccination  consideration  interpretation  determination  investigation  participation  representation  configuration  demonstration  exploitation  implementation  approximation  characterization  contamination  continuation  degeneration  depreciation  deterioration  manifestation  qualification  recommendation  reconciliation  rehabilitation  certification  disintegration  dissemination  dissociation  exaggeration  fragmentation  intoxication  optimization  privatization  pronunciation  purification  reorganization  signification  specialization  stabilization  subordination  transplantation  argumentation  capitalization  categorization  confederation  denunciation  devaluation  dispensation  exportation  extermination  hybridization  inactivation  intimidation  magnetization  magnification  nationalization  ornamentation  quantification  rationalization  segmentation  simplification  synchronization  visualization  administration  identification  differentiation  expectation  justification  precipitation  sophistication  stratification  decentralization  democratization  diversification  excommunication  instrumentation  personification  sedimentation  standardization  supplementation  specification  experimentation  industrialization  hospitalization  intensification  conceptualization  misrepresentation  Words that almost rhyme with decumulation
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