Here's what rhymes with decapitation.
                        
                        
                    
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proclamation  qualification  recommendation  rehabilitation  relaxation  resignation  segregation  specification  speculation  utilization  amplification  disintegration  fragmentation  generalization  humiliation  intoxication  localization  mobilization  multiplication  notification  optimization  privatization  pronunciation  remuneration  socialization  sophistication  stabilization  subordination  amalgamation  argumentation  authentication  calcification  conflagration  democratization  exclamation  hospitalization  hybridization  immunization  instrumentation  magnetization  menstruation  ornamentation  polymerization  prolongation  reclamation  sedimentation  standardization  communication  identification  transformation  accumulation  formulation  approximation  reconciliation  clarification  experimentation  liberalization  purification  signification  specialization  stratification  transplantation  unification  verification  centralization  crystallization  decentralization  deregulation  diversification  magnification  mortification  normalization  personification  rationalization  simplification  sterilization  synchronization  visualization  industrialization  reorganization  intensification  misrepresentation  nationalization  conceptualization  excommunication  Words that almost rhyme with decapitation
basin  haven  hasten  evasion  equation  occasion  invasion  persuasion  taken  pagan  bacon  patron  shaken  laden  maiden  layman  laymen  shaman  mistaken  undertaken  awaken  straighten  statesman  salesman  contagion  overtaken  tradesmen  forsaken