| part(noun, element) |
| prerequisite(noun, adjective, condition, essence, basic) |
| requisite(noun, adjective, condition, essence, basic) |
| rock bottom(expression, law, foundation, basic, stipulation) |
| rudiments |
| source(noun, support, action, start, top) |
| start(noun, rise, top, beginning, stone) |
| stem(noun, cause, element) |
| substratum(noun, support, action, base, beginning) |
| substructure(noun, basis) |
| support(noun, action, base, beginning, source) |
| undercarriage(fundamental, shorts) |
| underpinning(noun, support, action, base, beginning) |
| action(noun, support, base, beginning, source) |
| antecedent(noun, support, action, base, beginning) |
| aspect(noun, element) |
| assumption(noun, support, action, base, beginning) |
| authority(noun, support, action, base, beginning) |
| axiom(noun, law, support, action, base) |
| backbone(noun, support, action, base, beginning) |