| No. | Item | Definition |
|---|---|---|
| 1. | abstruse | hard to comprehend |
| 2. | ambiguous | open to more than one meaning |
| 3. | anonymous | of unknown name |
| 4. | arcane | known by only a few |
| 5. | baffling | impossibly confusing |
| 6. | barely visible | only just able to be seen |
| 7. | bewildering | very confusing |
| 8. | blanketed | completely covered over |
| 9. | blurred | made unclear or indistinct |
| 10. | blurry | not sharply clear |
| 11. | buried | hidden deep or covered |
| 12. | byzantine | excessively complicated |
| 13. | cloaked | hidden or disguised |
| 14. | cloudy | not clear or transparent |
| 15. | complicated | hard to understand or deal with |
| 16. | concealed | kept secret or out of sight |
| 17. | confusing | difficult to understand clearly |
| 18. | convoluted | overly complex and confusing |
| 19. | covered | hidden by something over it |
| 20. | covert | hidden and secret |
| 21. | cryptic | mysterious and hard to understand |
| 22. | dark | lacking light or clarity |
| 23. | dim | not bright or clear |
| 24. | dusky | somewhat dark or shadowy |
| 25. | eerie | strange and unsettling |
| 26. | effaced | wiped out or erased |
| 27. | elliptical | using hidden or omitted meaning |
| 28. | enigmatic | puzzling and hard to interpret |
| 29. | erased | removed from view or record |
| 30. | esoteric | understood by a small group |
| 31. | expunged | erased from a record |
| 32. | faded | become less clear or visible |
| 33. | faint | barely seen or heard |
| 34. | featureless | without clear distinguishing marks |
| 35. | forgotten | no longer remembered |
| 36. | fuzzy | unclear or imprecise |
| 37. | gloomy | dark and hard to see |
| 38. | hard to discern | difficult to detect clearly |
| 39. | hard to make out | difficult to see clearly |
| 40. | hazy | not clear or definite |
| 41. | hidden | kept from view or knowledge |
| 42. | impenetrable | impossible to understand clearly |
| 43. | imperceptible | too slight to notice |
| 44. | incomprehensible | impossible to understand |
| 45. | indecipherable | impossible to read or understand |
| 46. | indefinite | not clearly fixed or stated |
| 47. | indistinct | not clearly marked or seen |
| 48. | inscrutable | impossible to interpret |
| 49. | invisible | unable to be seen |
| 50. | involved | complicated and hard to follow |
| 51. | knotty | difficult to solve or understand |
| 52. | labyrinthine | extremely complicated and confusing |
| 53. | little-known | not widely known |
| 54. | lost | no longer found or known |
| 55. | low-profile | avoiding public attention |
| 56. | marginal | of limited importance |
| 57. | masked | concealed from view or understanding |
| 58. | missing | not present or found |
| 59. | misty | clouded or unclear |
| 60. | murky | dark, unclear, or confused |
| 61. | mysterious | difficult to explain or understand |
| 62. | mystifying | making something hard to understand |
| 63. | nameless | without a known name |
| 64. | nebulous | vague and ill-defined |
| 65. | neglected | given little attention |
| 66. | nondescript | lacking distinctive features |
| 67. | obliterated | completely destroyed or erased |
| 68. | odd | strange or unusual |
| 69. | opaque | not transparent in meaning |
| 70. | oracular | mysteriously hard to understand |
| 71. | out of sight | not visible |
| 72. | overlooked | not noticed or considered |
| 73. | peculiar | odd or distinctive |
| 74. | peripheral | not central or important |
| 75. | perplexing | causing confusion or uncertainty |
| 76. | puzzling | hard to understand or explain |
| 77. | quiet | not attracting much attention |
| 78. | recondite | difficult to understand |
| 79. | redacted | partly hidden in text |
| 80. | secret | kept hidden from others |
| 81. | shadowy | dim, vague, or uncertain |
| 82. | shrouded | covered or hidden from view |
| 83. | strange | unusual or unfamiliar |
| 84. | submerged | hidden beneath the surface |
| 85. | suppressed | deliberately kept from notice |
| 86. | tenebrous | dark and obscure |
| 87. | thorny | difficult and complicated |
| 88. | unclear | not easy to understand |
| 89. | underrated | not valued highly enough |
| 90. | unfamiliar | not well known |
| 91. | unintelligible | not understandable |
| 92. | unknown | not known or identified |
| 93. | unrecognized | not identified or acknowledged |
| 94. | unseen | not seen |
| 95. | unsung | not widely praised or known |
| 96. | vague | not clearly expressed or defined |
| 97. | vanished | disappeared from sight |
| 98. | veiled | partly concealed or disguised |
| 99. | weird | strange and hard to explain |
| 100. | withdrawn | removed from public view |