| No. | Item | Definition |
|---|---|---|
| 1. | all-important | supremely important |
| 2. | anchor | main supporting element |
| 3. | at the core of | fundamental to something |
| 4. | at the heart of | central to something |
| 5. | backbone | main supporting element |
| 6. | basic | forming the foundation |
| 7. | basis | foundation or starting point |
| 8. | bedrock | fundamental principle or basis |
| 9. | bound up with | closely connected to |
| 10. | built into | included as part of |
| 11. | built-in | included as a natural part |
| 12. | central | at the core of something |
| 13. | characteristic | typical and inherent |
| 14. | constituent | forming part of a whole |
| 15. | constituting | forming or making up |
| 16. | constitutive | forming an essential part |
| 17. | cornerstone | basic supporting element |
| 18. | critical | decisively important or serious |
| 19. | crucial | extremely important to success |
| 20. | decisive | settling an issue; crucial |
| 21. | deep-rooted | firmly established and inherent |
| 22. | defining | serving to identify essentially |
| 23. | determinative | decisive in shaping outcomes |
| 24. | dominant | most influential or important |
| 25. | embedded | firmly fixed within |
| 26. | entwined | closely linked together |
| 27. | epicenter | central point of activity |
| 28. | essential | absolutely necessary or central |
| 29. | fabric | basic structure of something |
| 30. | foremost | most important or prominent |
| 31. | forming | making up an essential part |
| 32. | foundational | serving as a basis |
| 33. | framework | basic supporting structure |
| 34. | fulcrum | central point of support |
| 35. | fundamental | forming the basic core |
| 36. | germane | closely relevant |
| 37. | grave | seriously important |
| 38. | groundwork | basic foundation for something |
| 39. | hardwired | built in as essential |
| 40. | heart | central or most important part |
| 41. | hinge | central point of dependence |
| 42. | hub | central point or part |
| 43. | immanent | existing within something |
| 44. | imperative | urgently necessary |
| 45. | incorporated | included as part |
| 46. | indispensable | too important to do without |
| 47. | inherent | existing as a natural part |
| 48. | inseparable | unable to be separated |
| 49. | institutional | firmly established as part |
| 50. | intrinsic | belonging naturally; essential |
| 51. | key | of central importance |
| 52. | keystone | central supporting element |
| 53. | leading | most important or principal |
| 54. | lifeblood | indispensable sustaining force |
| 55. | linchpin | thing holding others together |
| 56. | linked to | connected in an important way |
| 57. | main | chief in importance |
| 58. | mainstay | chief support or element |
| 59. | major | very important or significant |
| 60. | mandatory | required by rule or need |
| 61. | mission-critical | essential for operation or success |
| 62. | must-have | something essential to have |
| 63. | necessary | needed for a purpose |
| 64. | needed | required or essential |
| 65. | nerve center | main controlling point |
| 66. | nonnegotiable | not open to omission |
| 67. | nonoptional | not optional; required |
| 68. | nucleus | central and most important part |
| 69. | obligatory | required; not optional |
| 70. | of consequence | important enough to matter |
| 71. | of moment | important or significant |
| 72. | of note | worth attention; important |
| 73. | of the essence | absolutely necessary or central |
| 74. | organic | naturally forming part of something |
| 75. | overriding | more important than others |
| 76. | paramount | more important than anything else |
| 77. | part and parcel | an essential part |
| 78. | pertinent | relevant to the matter |
| 79. | pivotal | of vital importance |
| 80. | preeminent | surpassing others in importance |
| 81. | preponderant | having greatest importance |
| 82. | primary | first in importance |
| 83. | principal | most important |
| 84. | relevant | closely connected to the topic |
| 85. | required | officially or practically needed |
| 86. | requisite | required or necessary |
| 87. | salient | especially noticeable or important |
| 88. | seminal | strongly influential and foundational |
| 89. | soul | essential spirit or core |
| 90. | staple | basic and important element |
| 91. | structural | forming the framework |
| 92. | supreme | highest in importance |
| 93. | tied to | closely connected with |
| 94. | touchstone | key standard or basis |
| 95. | underpinning | supporting foundation or basis |
| 96. | urgent | needing prompt action |
| 97. | vital | critically important or necessary |
| 98. | warp and woof | essential structure or substance |
| 99. | weighty | important and serious |
| 100. | woven into | made part of closely |
