plaque

1. 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. (countable)
2. 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. (countable)
3. A small card representing an amount of money, used for betting in casinos; a sort of gaming chip. (countable)
4. A clearing in a bacterial lawn caused by a virus. (countable)
5. In the Hornbostel–Sachs classification system: any flat, thin musical instrument. (countable) · blown plaques· aconcussion plaques
6. A broad patch of abnormal tissue distinguishable from surrounding tissue, especially a broad papule (“inflamed, irritated patch”) on the skin. (countable)
7. An abnormal accumulation of material in or on an organ of the body, often associated with disease. (countable, uncountable) · amyloid plaque· apleural plaque
8. An accumulation in artery walls made up of macrophage cells and debris containing lipids, (cholesterol and fatty acids), calcium, and connective tissue; an atheroma. (countable, uncountable)

Plural plaques