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100 Best Synonyms for “Ominous”

June 20, 2026

100 Best Synonyms for

No. Item Definition
1. accursed under a curse; doomed
2. adverse unfavorable and harmful
3. alarming causing worry about danger
4. apocalyptic suggesting catastrophic destruction
5. awful very bad or alarming
6. baleful harmful-looking and full of menace
7. baneful causing harm or ruin
8. black gloomy and threatening in tone
9. bleak cold, grim, and hopeless
10. brooding darkly thoughtful and threatening
11. brutal harshly violent or cruel
12. calamitous bringing great disaster or distress
13. catastrophic involving disastrous consequences
14. charged filled with tense significance
15. cold-eyed showing harsh, dangerous intent
16. creepy uneasily frightening or sinister
17. critical serious and possibly dangerous
18. dangerous likely to cause harm
19. dark suggestively grim or threatening
20. deathly suggesting death or dread
21. dire warning of very serious trouble
22. disastrous likely to end very badly
23. disquieting causing unease or anxiety
24. disturbing causing anxiety or alarm
25. doomy suggesting doom or disaster
26. eerie strange and frightening
27. evil-looking appearing wicked or dangerous
28. explosive likely to erupt violently
29. fatal causing death or disaster
30. fateful charged with serious consequences
31. fearsome inspiring fear or alarm
32. foreboding creating a sense of coming trouble
33. fraught full of something troubling
34. frightening causing fear or apprehension
35. funereal darkly mournful and deathlike
36. ghastly frighteningly grim or dreadful
37. gloomy dark and depressing; threatening
38. grave serious and worrying
39. grim harsh, gloomy, and threatening
40. grisly horribly grim or gruesome
41. gruesome causing horror or disgust
42. hard-edged severe and threatening
43. haunting disturbingly suggestive or lingering
44. hazardous involving danger or risk
45. heavy oppressively serious or threatening
46. horrific extremely frightening or dreadful
47. hostile showing opposition or threat
48. ill-boding suggesting bad things ahead
49. ill-fated destined for bad outcomes
50. ill-starred marked by bad luck
51. implacable unable to be calmed
52. inauspicious not favorable; suggesting bad outcomes
53. intimidating frightening or overawing
54. loaded carrying serious hidden implications
55. lowering darkly threatening in appearance
56. lurid shocking and ominously vivid
57. macabre disturbingly connected with death
58. malign harmful in intent or effect
59. menacing appearing likely to cause harm
60. merciless showing no mercy
61. morbid disturbingly focused on death
62. murky dark and vaguely threatening
63. nightmarish frightening like a nightmare
64. noxious harmful or poisonous
65. oppressive heavy, harsh, and threatening
66. overcast darkened and gloomy
67. perilous full of danger or risk
68. pitiless without pity or compassion
69. poisonous harmful in a dangerous way
70. portentous signaling something serious or bad
71. precarious dangerously uncertain or unstable
72. prophetic suggesting what will happen
73. relentless continuing harshly without stopping
74. remorseless without regret or pity
75. risky likely to involve danger
76. ruthless showing no mercy or pity
77. scary causing fear or unease
78. sepulchral gloomy like a tomb
79. serious weighty and potentially troubling
80. shadowy dim, secretive, and threatening
81. sinister suggesting evil or danger
82. somber dark and serious in mood
83. spooky frightening in a ghostly way
84. stormy full of conflict or threat
85. tempestuous violently turbulent and threatening
86. terrifying causing extreme fear
87. threatening suggesting danger or harm
88. thunderous suggesting violent trouble ahead
89. tragic suggesting terrible suffering or loss
90. troubling causing concern or unease
91. uncanny strangely unsettling or suggestive
92. unnerving making people feel uneasy
93. unpromising not likely to end well
94. unsafe not safe; potentially harmful
95. unsettling making people feel disturbed
96. venomous full of malice or danger
97. vicious deliberately cruel or violent
98. volatile likely to become dangerous suddenly
99. wicked evil or morally wrong
100. worrying causing concern about outcomes
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