plaque

American  

[plak] / plæk /

noun

plaques plural

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

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

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

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

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

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

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plaque British  

/ plæk, plɑːk /

noun

1. an ornamental or commemorative inscribed tablet or plate of porcelain, wood, etc

2. a small flat brooch or badge, as of a club, etc

3. pathol any small abnormal patch on or within the body, such as the typical lesion of psoriasis

4. short for dental plaque

5. bacteriol a clear area within a bacterial or tissue culture caused by localized destruction of the cells by a bacteriophage or other virus

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plaque Scientific  

/ plăk /

1. A small disk-shaped formation or growth; a patch.

2. A film of mucus and bacteria on the surface of the teeth.

3. A deposit of material in a bodily tissue or organ, especially one of the fatty deposits that collect on the inner lining of an artery wall in atherosclerosis or one of the amyloid deposits that accumulate in the brain in Alzheimer's disease.

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plaque Cultural  

1. A thin film composed of bacteria, mucus, and food particles that forms on the surfaces of teeth. Plaque contributes to tooth decay and gum disease. Plaque also refers to a combination of cholesterol and lipids that can accumulate on the inside of arteries, causing atherosclerosis.

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Other Word Forms

Noun Inflected Forms

• plaques
  plural

Etymology

Origin of plaque

1840–50; < French, noun derivative of plaquer to plate < Middle Dutch placken to patch; cf. placket

Explanation

A plaque is a sign that memorializes a person or event, such as the plaque on a building noting the person it's named after or the year it was built. Plaque comes from the French word for "plate," meaning not a dinner plate, but a little brass or tin plate that can be mounted on a wall. If you take a tour of Civil War battlefields, you'll find that historical societies often use plaques to commemorate soldiers or particular events. Plaque is also a hard buildup in the body, like the plaque on your teeth that the dentist likes to scrape off.

Example Sentences

A small plaque lists a phone number and urges visitors to dial it “if you notice damage or vandalism to this mural.”

From Los Angeles Times • Jun. 19, 2026

Mice lacking the receptor developed significantly less plaque in the aorta and aortic arch, although some plaque remained in the pulmonary artery.

From Science Daily • Jun. 9, 2026

One plaque will be installed at the Open University in Milton Keynes, where Beagle 2 was conceived by Professor Colin Pillinger.

From BBC • Jun. 9, 2026

Doctors must administer high doses of Eisai/Biogen’s Leqembi and Lilly’s Kisunla, because only a fraction of 1% of the infused antibodies reach the amyloid plaque that chokes brain cells in Alzheimer’s.

From Barron's • Jun. 3, 2026

“She’s on this plaque in the office—the school’s SAT record—a near perfect score!”

From "Dry" by Neal Shusterman and Jarrod Shusterman

Related Words

• badge
• decoration
• medal
• nameplate
• plate
• slab