n. A vessel or melting-pot for chemical purposes, made of pure clay or other material, as black-lead, porcelain, platinum, silver, or iron, and so baked or tempered as to endure extreme heat without fusing.n. A hollow place at the bottom of a chemical furnace, for collecting the molten metal.n. Figuratively, a severe or searching test: as, his probity was tried in the crucible of temptation.n.