root

1 a point or place at which something is invented or provided he insists that insecurity is the root of all jealousy Synonyms cradle, font, fountain, fountainhead, origin, source, seedbed, spring, well, wellspringRelated Words beginning, commencement, dawn, day one, genesis, get-go (also git-go), inception, incipience, incipiency, kickoff, launch, morning, nascence, nascency, onset, outset, start, threshold; baseline, first base, ground zero, square one

2 the source from which something grows or develops one would need to go back at least several hundred years to find the root of the entrenched hostility between the neighboring nations Synonyms fountainhead, germ, origin, seed, seedbedRelated Words font, fountain, spring, well, wellhead, wellspring; beginning, birth, commencement, dawn, genesis, inception, incipiency, launch, morning, onset, outset, start, threshold; creation, inauguration, origination

3 an immaterial thing upon which something else rests an implicit trust in the wisdom of the people is the root of democracy Synonyms basis, bedrock, bottom, cornerstone, footing, foundation, ground, groundwork, keystone, base, underpinning, warp, warp and woofRelated Words anchorage, bed, brace, bulwark, buttress, framework, infrastructure, mount, prop, shore, stay, substratum, substructure, support; assumption, justification, premise (also premiss), presumption, presupposition, rationale, supposition, theory, thesis, warrant; backbone, center, core, cornerstone, eye, focus, heart, hub, kernel, keystone, nucleus, seat; essence, quintessence, soul, touchstone

4 the central part or aspect of something under consideration at root, it's a question of the proper limits, if any, of free speech Synonyms bottom line, bull's-eye, centerpiece, core, essence, gist, heart, kernel, keynote, meat, meat and potatoes, net, nub, nubbin, nucleus, pith, pivot, point, crux, sumRelated Words course, direction, drift, tenor; body, content, substance; hypothesis, proposition, purport, subject, theme, thesis