a thin, flat plate or tablet of metal, porcelain, etc., intended for ornament, as on a wall, or set in a piece of furniture.

an inscribed commemorative tablet, usually of metal placed on a building, monument, or the like.

a platelike brooch or ornament, esp. one worn as the badge of an honorary order.

Anatomy, Pathology . a flat, often raised, patch on the skin or other organ, as on the inner lining of arterial walls in atherosclerosis.

Dentistry . a soft, sticky, whitish matlike film attached to tooth surfaces, formed largely by the growth of bacteria that colonize the teeth.

Bacteriology . a cleared region in a bacterial culture, resulting from lysis of bacteria by bacteriophages.

noun

badge , brooch , decoration , disk , medal , memorial , nameplate , patch , plate , slab