1 an ornamental tablet of metal, porcelain, etc., esp. affixed to a building in commemoration.
2 a deposit on teeth where bacteria proliferate.
3 Med. a a patch or eruption of skin etc. as a result of damage. b a fibrous lesion in atherosclerosis.
4 a small badge of rank in an honorary order.
Derivatives:
plaquette n.
Etymology: F f. Du. plak tablet f. plakken stick
Useful english dictionary. 2012.