| No. | Item | Definition |
|---|---|---|
| 1. | accountable | required to explain or answer |
| 2. | answerable | required to answer for something |
| 3. | antecedent | required or existing before |
| 4. | appropriate | needed or suitable for the situation |
| 5. | assigned | required as a task |
| 6. | bare | only what is necessary |
| 7. | baseline | minimum required level |
| 8. | basic | forming a needed foundation |
| 9. | binding | requiring legal obedience |
| 10. | business-critical | essential to business operations |
| 11. | called-for | needed in the circumstances |
| 12. | central | most important and essential |
| 13. | compelling | forcing or requiring action |
| 14. | compulsory | required, not optional |
| 15. | contractual | required by a contract |
| 16. | critical | essential to success or safety |
| 17. | crucial | extremely important and needed |
| 18. | customary | required by custom or practice |
| 19. | decisive | determining the result |
| 20. | demanded | insisted on as required |
| 21. | demanding | requiring effort or attention |
| 22. | dependent | requiring something else |
| 23. | dictated | required by circumstances |
| 24. | directed | required by instruction |
| 25. | due | owed or required |
| 26. | elementary | basic and necessary |
| 27. | enabling | needed to make something possible |
| 28. | enforced | made compulsory by authority |
| 29. | essential | absolutely needed or very important |
| 30. | exacting | requiring much care or effort |
| 31. | exigent | requiring immediate attention |
| 32. | expected | required as normal behavior |
| 33. | fit | suitable and needed |
| 34. | fitting | suitable and called for |
| 35. | forced | made necessary or compulsory |
| 36. | foremost | most important |
| 37. | foundational | basic and necessary |
| 38. | functional | needed for proper working |
| 39. | fundamental | basic and essential |
| 40. | imperative | urgently required or unavoidable |
| 41. | important | having great need or value |
| 42. | imposed | required by authority |
| 43. | incumbent | required as a duty |
| 44. | indispensable | too important to do without |
| 45. | inescapable | impossible to escape or avoid |
| 46. | inevitable | certain and unavoidable |
| 47. | instructed | required by direction |
| 48. | integral | needed as part of a whole |
| 49. | key | very important and necessary |
| 50. | labor-intensive | requiring much work |
| 51. | laid-down | formally set as required |
| 52. | liable | legally required or responsible |
| 53. | life-or-death | vitally necessary for survival |
| 54. | life-sustaining | needed to keep life going |
| 55. | lifesaving | needed to prevent death |
| 56. | main | chief or most important |
| 57. | major | very important or necessary |
| 58. | mandatory | required by law or rule |
| 59. | minimal | least necessary |
| 60. | minimum | least amount required |
| 61. | mission-critical | essential to a mission’s success |
| 62. | must-do | something essential to do |
| 63. | must-have | something essential to have |
| 64. | necessitous | in need or requiring help |
| 65. | needed | wanted because it is required |
| 66. | needful | necessary or required |
| 67. | nonnegotiable | not open to change or refusal |
| 68. | obligatory | required by duty or rule |
| 69. | operational | needed for practical functioning |
| 70. | ordained | officially ordered or required |
| 71. | ordered | required by command |
| 72. | payable | required to be paid |
| 73. | prerequisite | required before something else |
| 74. | prescribed | officially required or ordered |
| 75. | pressing | needing immediate attention |
| 76. | primary | most important or basic |
| 77. | principal | main and important |
| 78. | procedural | required by process or procedure |
| 79. | proper | required by correctness or suitability |
| 80. | regulatory | required by regulations |
| 81. | required | needed by rule or circumstance |
| 82. | requisite | needed for a particular purpose |
| 83. | responsible | required to answer or act |
| 84. | right | suitable and required |
| 85. | root | basic and essential |
| 86. | rudimentary | basic and necessary |
| 87. | set | established and required |
| 88. | specified | stated as required |
| 89. | standard | normally required or expected |
| 90. | statutory | required by law |
| 91. | stipulated | specified as required |
| 92. | suitable | right and needed for a purpose |
| 93. | survival | needed for continued existence |
| 94. | sustaining | needed to keep something going |
| 95. | technical | required by technical rules |
| 96. | time-sensitive | requiring action before a deadline |
| 97. | unavoidable | impossible to avoid |
| 98. | underlying | basic and necessary beneath something |
| 99. | urgent | needing quick action |
| 100. | vital | needed for life or success |
