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100 Best Synonyms for “Doubtful”

July 1, 2026

100 Best Synonyms for

No. Item Definition
1. alleged claimed but unproven
2. ambiguous having more than one meaning
3. arguable open to debate
4. at issue under dispute or discussion
5. baseless without foundation in fact
6. challenged disputed or questioned
7. chancy uncertain and risky
8. cloudy unclear or doubtful
9. conjectural based on guesswork
10. contested disputed or challenged
11. controvertible able to be disputed
12. debatable open to argument or doubt
13. dicey risky or uncertain
14. disputable able to be questioned
15. dubious questionable or uncertain
16. equivocal not clear or definite
17. erroneous wrong or possibly wrong
18. faint small and uncertain
19. false not true
20. far-fetched unlikely to be true
21. fishy suspicious or doubtful
22. flimsy weak and unconvincing
23. foggy unclear in thought or detail
24. groundless having no valid basis
25. hard to accept difficult to believe
26. hard to believe difficult to accept as true
27. hard to credit difficult to believe
28. hazy unclear or uncertain
29. hypothetical assumed but unproven
30. iffy uncertain or unreliable
31. implausible not seeming believable
32. improbable not likely to be true
33. in doubt not certain
34. in question being doubted or examined
35. incorrect not right or accurate
36. incredible too unlikely to believe
37. indefinite not exact or fixed
38. indeterminate not clearly determined
39. invalid not sound or valid
40. liable to question subject to doubt
41. mistrusted not trusted
42. moot open to debate
43. murky unclear or confusing
44. nebulous vague and unclear
45. not certain lacking certainty
46. not clear uncertain or ambiguous
47. not confirmed lacking confirmation
48. not definite not clearly fixed
49. not final still subject to change
50. not proven lacking proof
51. not settled not finally decided
52. not sure uncertain
53. obscure not clearly understood
54. open not finally decided
55. ostensible appearing true but doubtful
56. ostensibly true apparently true but uncertain
57. pending awaiting decision or confirmation
58. poorly founded based on weak evidence
59. precarious uncertain and risky
60. presumed believed but not certain
61. problematic causing doubt or difficulty
62. professed claimed, not necessarily genuine
63. provisional temporary and not final
64. purported claimed but not proven
65. putative generally supposed, not certain
66. questionable open to doubt
67. questioned subject to doubt
68. remote unlikely to happen
69. reported stated but not confirmed
70. rumored said but unconfirmed
71. shaky not firm or reliable
72. slight small in likelihood
73. slim small or doubtful in chance
74. so-called named but doubted
75. speculative based on guesswork
76. strained not natural or convincing
77. supposed claimed but uncertain
78. suspect not fully trustworthy
79. suspicious causing distrust or doubt
80. tentative not final or certain
81. tenuous weak or uncertain
82. theoretical possible but not proven
83. thin lacking strong support
84. touch-and-go very uncertain in outcome
85. uncertain not known or decided
86. unclear not clear or certain
87. unconfirmed not officially verified
88. undecided not yet decided
89. unfounded not based on facts
90. unlikely not expected to happen
91. unproven not shown to be true
92. unresolved not settled or answered
93. unsettled not decided or resolved
94. unsubstantiated not supported by evidence
95. unsupported lacking evidence or backing
96. unsure not feeling certain
97. unverified not proven true
98. vague not clearly expressed
99. weak not convincing or strong
100. weakly supported lacking strong evidence
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