plaque
UK[plɑːk]US[plæk]
n
a flat piece of stone, metal, or wood, often with writing on it, used as a memorial or marker.
n
a sticky, colorless film of bacteria and sugars that forms on teeth.
n
a small, distinct, often raised patch or area on the skin or within the body.
Etymology
the word "plaque" entered english in the mid-19th century, borrowed directly from the french word "plaque" meaning a "plate, slab, or sheet." the french term itself derives from the middle dutch "placke," meaning a "disk, patch, or stain," which is likely of germanic origin. the core semantic thread from its origins is that of a flat, thin, often rigid object. this literal meaning evolved in english to cover commemorative tablets, bacterial films on teeth (conceptualized as a coating), and abnormal patches on body tissue, all sharing the fundamental idea of a distinct layer or deposit on a surface.
Analysis
the word is a simplex loanword from french. it is not productively formed from smaller, recognizable english morphemes.
Examples
a bronze plaque on the wall commemorates the building's history.
regular brushing helps to remove plaque and prevent cavities.
the doctor identified a small fatty plaque in the artery.