1. necessary absolutely essential
  2. necessarily in such a manner as could not be otherwise
  3. unnecessary not needed
  4. necessity the condition of being essential or indispensable
  5. unnecessarily without any necessity
  6. necessitarian someone who does not believe the doctrine of free will
  7. incessant uninterrupted in time and indefinitely long continuing
  8. recession the act of returning control
  9. assessor an official who evaluates property in order to tax it
  10. nefarious extremely wicked
  11. accessary someone who helps another person commit a crime
  12. concession the act of yielding
  13. necessitate require as useful, just, or proper
  14. accessory a supplementary component that improves capability
  15. scenario a postulated sequence of possible events
  16. necessitous poor enough to need help from others
  17. secession formal separation from an alliance or federation
  18. possessor a person who owns something
  19. recessionary of or pertaining to a recession
  20. Secession the withdrawal of eleven southern states from the Union in 1860 which precipitated the American Civil War

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