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Medical Dictionary

plaque

noun

Medical Definition of plaque

  1. 1a:  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 bacteriac:  an atherosclerotic lesiond:  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. 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



Variants of plaque

also placque \ˈplak\play


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