plaque

noun

ˈplak 

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

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 on the Web

The interior, meanwhile, has been left nearly untouched, with the exception of a plaque identifying the vehicle as part of the project. —Bryan Hood, Robb Report, 12 Jan. 2026

Individualism gets you trophies and plaques. —Assistant Sports Editor, Los Angeles Times, 12 Jan. 2026

At Tillis' urging, the Senate voted by a procedure known as unanimous consent to make any changes needed to the original law in order to get the plaque installed once and for all. —CBS News, 11 Jan. 2026

The synagogue's Tree of Life plaque honoring congregants' meaningful occasions was destroyed. —Kristin Wright, NPR, 11 Jan. 2026

Word History

Etymology

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

First Known Use

1845, in the meaning defined at sense 1a

Phrases Containing plaque

• anti-plaque

Rhymes for plaque

• ack
• brack
• clack
• crack
• dak
• flack
• flak
• hack
• jack
• knack
• lac
• lack

Kids Definition

plaque

noun

ˈplak 

1

: an ornamental pin

especially : an honorary badge

2

: a flat thin piece (as of metal) used for decoration or inscribed as a memorial or marker

3

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

Medical Definition

plaque

noun

variants also placque

ˈplak 

1

a

: a localized abnormal patch on a body part or surface and especially on the skin

psoriatic plaque

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

called also senile plaque

2

: a visibly distinct and especially a clear or opaque area in a bacterial culture produced by damage to or destruction of cells by a virus