bedrock

1 an immaterial thing upon which something else rests my religious faith is the bedrock of my life Synonyms basis, base, bottom, cornerstone, footing, foundation, ground, groundwork, keystone, root, 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

2 the lowest point or level knew that his acting career was at bedrock when all he could get were bit parts in campy horror movies Synonyms nadir, bottom, depth, rock bottom, zeroRelated Words abyss, armpit, pitNear Antonyms bloom, flood tide, flower, glory, heyday; crescendo, high; cap, ceiling, crest, roofAntonyms acme, apex, climax, crown, culmination, head, height, high-water mark, meridian, peak, pinnacle, summit, tip-top, top, zenith