| 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: | groundwork |
| Part of Speech: | noun |
| Definition: | basis, fundamentals |
| Synonyms: | ABCs, background, base, bedrock, cornerstone*, footing, foundation, ground, infrastructure, origin, preliminaries, preparation, root, substratum, underpinning, understructure |
| Main Entry: | keynote/keystone |
| Part of Speech: | noun |
| Definition: | essence, theme |
| Synonyms: | basic idea, basis, center, core, cornerstone, criterion, crux, gist, heart, idea, kernel, linchpin, mainspring, marrow, measure, motive, nub, pith, principle, root, source, spring, standard, substance |
| Main Entry: | rock |
| Part of Speech: | noun |
| Definition: | foundation |
| Synonyms: | Rock of Gibraltar, anchor, bulwark, cornerstone, defense, mainstay, protection, strength, support |
| Main Entry: | support |
| Part of Speech: | noun |
| Definition: | something that holds up structure |
| Synonyms: | abutment, agency, back, backing, base, bed, bedding, block, brace, buttress, collar, column, cornerstone, device, flotation, foothold, footing, foundation, fulcrum, groundwork, guide, hold, lining, means, medium, pillar, platform, pole, post, prop, rampart, reinforcement, rest, rib, rod, shore, stake, stanchion, stave, stay, stiffener, stilt, substratum, substructure, sustentation, timber, underpinning |
| 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 |
| Main Entry: | quoin |
| Part of Speech: | noun |
| Definition: | keystone |
| Synonyms: | angle, cornerstone, wedge |
| Main Entry: | keystone |
| Part of Speech: | noun |
| Definition: | base |
| Synonyms: | cornerstone, crown, foundation, headstone, mainstay, principle, root, support, wedge |
| Main Entry: | rudiment |
| Part of Speech: | noun |
| Definition: | basis |
| Synonyms: | base, bed, bottom, cornerstone, foot, footing, foundation, fundament, fundamental, ground, groundwork, rest, resting place, root, seat, substructure, support |