Enamel  —n. 1 glasslike opaque ornamental or preservative coating on metal etc. 2 a smooth hard coating. B a kind of hard gloss paint. C cosmetic simulating this, esp. Nail varnish. 3 hard coating of a tooth. 4 painting done in enamel. —v. (-ll-; us -l-) inlay, coat, or portray with enamel.