Synonyms:
(Adjective)
  1. doubtingly
  2. doubtfully
  3. skeptically
  4. dubiously
  5. uncertainly
  6. distrustfully
  7. distrustingly
  8. unbelievingly
  9. questioningly
  10. problematically
  11. in doubt
  12. in a doubtful manner
  13. causing suspicion
  14. encouraging suspicion
  15. with caution
  16. with reservation
  17. with some reservation
  18. not gullibly
  19. not wholeheartedly
  20. not without reservations
  21. not without doubts
  22. with-a-grain-of-salt
  23. with a pinch of salt
  24. cum grano salis (Latin);
  25. like a doubting Thomas

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