| basal(adjective, body, start, simple, plain) |
| chief(adjective, important, significant, essential, prime) |
| natural(adjective, characteristic, body, simple, rough) |
| plain(adjective, clear, light, smooth, simple) |
| introductory(adjective, start, simple, plain, head) |
| primitive(adjective, body, simple, plain, material) |
| radical(adjective, base, important, significant, last) |
| bare(adjective, hard, simple, severe, plain) |
| central(adjective, important, significant, original, essential) |
| indispensable(adjective, characteristic, important, significant, natural) |
| initial(adjective, start, simple, plain, head) |
| staple(noun, adjective, set, usual, regular) |
| unadorned(adjective, hard, simple, severe, plain) |
| ultimate(adjective, essential, surface, fundamental, supreme) |
| critical(adjective, severe, important, original, essential) |
| crucial(adjective, important, significant, original, essential) |
| deep-seated(adjective, characteristic, natural, original, essential) |
| innate(adjective, characteristic, material, natural, gut) |
| requisite(noun, adjective, important, want, significant) |
| stark(adjective, direct, simple, severe, plain) |