plaque

Any flat, thin piece of clay, ivory, metal, etc., used for ornament, or for painting pictures upon, as a dish, plate, slab, etc., hung upon a wall; also, a smaller decoration worn by a person, such as a brooch.

A piece of flat metal with writing on it, attached to a building, monument, or other structure to remind people of a person or an event.

An abnormal accumulation of material in or on an organ of the body, often associated with disease.