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100 Best Synonyms for “Invalid”

June 20, 2026

100 Best Synonyms for

No. Item Definition
1. abrogated formally abolished or annulled
2. annulled declared legally void
3. bad wrong or unacceptable
4. banned officially not allowed
5. barred prevented by rule or law
6. baseless without foundation or evidence
7. bogus fake or not genuine
8. canceled called off or made void
9. counterfeit made to deceive as genuine
10. defective faulty or not valid
11. deficient lacking what is required
12. disallowed not accepted or permitted
13. disputable open to question or doubt
14. disqualified declared not eligible
15. doubtful not certain or reliable
16. dubious doubtful or suspect
17. erroneous containing an error
18. excluded not allowed to be included
19. expired no longer valid
20. fake not genuine
21. fallacious based on faulty reasoning
22. false not true
23. faulty containing errors or flaws
24. flawed imperfect or defective
25. forbidden not allowed
26. forged falsely made or altered
27. fraudulent involving deceit or falsification
28. groundless without a valid basis
29. illegal against the law
30. illegitimate not legally or properly valid
31. illogical not logically sound
32. impermissible not permitted under rules
33. improper not correct or acceptable
34. inaccurate not exact or correct
35. inadmissible not acceptable as evidence
36. incorrect not correct
37. indefensible unable to be justified
38. ineffective not producing legal effect
39. inoperative not functioning or effective
40. invalidated made invalid or ineffective
41. irregular not following required rules
42. lacking missing a required element
43. lapsed no longer valid after expiry
44. late after the required time
45. nonbinding not legally enforceable
46. noncompliant not meeting rules or standards
47. nonconformant not conforming to standards
48. nonconforming not meeting specified requirements
49. nonstandard not meeting usual standards
50. null having no legal effect
51. nullified made legally invalid
52. obsolete no longer valid or used
53. of no effect having no force
54. out of order not procedurally proper
55. outdated no longer current or valid
56. outlawed made illegal or banned
57. prohibited formally not allowed
58. proscribed officially forbidden
59. quashed officially made void
60. questionable doubtful or suspect
61. rejected not accepted as valid
62. rescinded formally canceled or withdrawn
63. revoked officially taken back
64. set aside canceled by legal authority
65. sham fake or not genuine
66. specious seemingly right but false
67. spurious not genuine or valid
68. stale too old to be valid
69. substandard below required standard
70. suspect doubtful or not trustworthy
71. ultra vires beyond legal authority
72. unacceptable not meeting required standards
73. unallowable not permitted or acceptable
74. unapproved not officially accepted
75. unauthenticated not proven genuine
76. unauthorized not officially permitted
77. uncertified not officially verified or approved
78. unconstitutional contrary to a constitution
79. uncorroborated not supported by other evidence
80. unenforceable not able to be enforced
81. unfounded not based on evidence
82. unjustified not supported by good reasons
83. unlawful not allowed by law
84. unlicensed lacking required legal permission
85. unproven not shown to be true
86. unreasonable not sensible or justified
87. unrecognized not officially accepted or acknowledged
88. unregistered not officially recorded as valid
89. unsound not valid or reliable
90. unsubstantiated not supported by proof
91. unsupported not backed by evidence
92. untenable impossible to defend reasonably
93. untrue not true
94. unverified not confirmed as true
95. unwarranted not justified or authorized
96. void having no legal effect
97. voided made legally ineffective
98. wanting lacking what is needed
99. wrong not correct or true
100. wrongful unlawful or improper

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