Main Entry:

plaque

Pronunciation:

\ˈplak\

Function:

noun

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

Date:

1845

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 tablet2 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 dendrites3: a clear area in a bacterial culture produced by viral destruction of cells