plaque

noun \ ˈplak \

Updated on: 12 May 2018

Definition of plaque

1 a : an ornamental brooch; especially : the badge of an honorary order

b : a flat thin piece (as of metal) used for decoration

c : a commemorative or identifying inscribed tablet

2 a : a localized abnormal patch on a body part or surface

b : a sticky usually colorless film on teeth that is formed by and harbors bacteria

c : an atherosclerotic lesion

d : a histopathologic lesion of brain tissue that is characteristic of Alzheimer's disease and consists of a dense proteinaceous core composed primarily of beta-amyloid that is often surrounded and infiltrated by a cluster of degenerating axons and dendrites

3 : a clear area in a bacterial culture produced by viral destruction of cells

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Examples of plaque in a Sentence

A bronze plaque marked the city's oldest building.
They gave him a plaque in honor of his 30 years of service.
Brushing your teeth prevents the buildup of plaque.
The scientists are studying the way the plaques form.

Recent Examples of plaque from the Web

For somewhere between $300 and $4,000 per year, depending on the size of the building, Rentlogic will certify its grade and provide a plaque for the company to display.

— jessi hempel, WIRED, "Want to Prove Your Business Is Fair? Audit Your Algorithm," 9 May 2018
However, a short distance away, nestled under a grandfather oak is a humble plaque bedecked with happy little squirrels.

— vincent crampton, OrlandoSentinel.com, "Explore Florida's Orange County: Woodlawn Memorial Park’s happy little plot," 6 May 2018
But Nasr’s is the only body identified as being there, by a wooden plaque.

— judith h. dobrzynski, WSJ, "A Final Resting Place, Both Beguiling and Beautiful," 4 May 2018
Each donor’s name will be placed on a plaque at the base of each flag pole.

— vanesa brashier, Houston Chronicle, "Dayton Memorial American Legion Post 512 moves into new headquarters," 30 Apr. 2018
Cardinal Gibbons High School Athletic Hall of Fame inductee Jenna Romanelli, left, proudly holds her plaque while sharing a special moment with her girls volleyball coach Louise Crocco in the school’s gymnasium.

— emmett hall, Sun-Sentinel.com, "Lighthouse Point resident inducted into Cardinal Gibbons Athletic Hall of Fame," 28 Apr. 2018
Gault raced past his plaque on the Penn Relays Wall of Fame in the Mixed Masters relay.

— phil anastasia, Philly.com, "Masters sprinter Willie Gault still going strong at Penn Relays," 27 Apr. 2018
The winners also received a plaque from the pageant director, Lynn Ross.

— elizabeth marie himchak, Rancho Bernardo, "New Miss Rancho Bernardo, Miss Teen RB crowned," 25 Apr. 2018
Foley's casket was laid to rest next to a memorial plaque for his predecessor, Bishop Raymond Boland, who served as bishop of Birmingham from 1988-93.

— greg garrison, AL.com, "Bishop Foley buried at cathedral," 23 Apr. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'plaque.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of plaque

French, from Middle French, metal sheet, from plaquer to plate, from Middle Dutch placken to piece, patch; akin to Middle Dutch placke piece, Middle High German placke patch

NEW! Time Traveler

First Known Use: 1845

in the meaning defined at sense 1a

See Words from the same year

Other Dentistry Terms

bridge, crown, tush

PLAQUE Defined for English Language Learners

plaque

noun

Definition of plaque for English Language Learners

: a flat, thin piece of metal or wood with writing on it that is used especially as a reminder of something (such as a historic event or an achievement)
: a thin coating that forms on teeth and contains bacteria
medical : a change in brain tissue that occurs in Alzheimer's disease