| Main Entry: | |
| Part of Speech: | noun |
| Definition: | vital element |
| Synonyms: | anchor, base, essential, foundation, key element, keystone, linchpin, main ingredient, mainspring, mainstay, pillar |
| Main Entry: | mainstay |
| Part of Speech: | noun |
| Definition: | chief support |
| Synonyms: | anchor, backbone, brace, bulwark, buttress, crutch, good right arm, linchpin, maintainer, pillar, prop, right-hand person, sinew, staff, standby, stay, strength, supporter, sustainer, upholder |
| Main Entry: | keynote |
| Part of Speech: | noun |
| Definition: | theme |
| Synonyms: | basic idea, basis, center, core, cornerstone, criterion, crux, essence, gist, heart, idea, kernel, keystone, linchpin, mainspring, marrow, measure, motive, nub, pith, principle, root, source, spring, standard, substance |