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Medical Term:


Pronunciation: mī-krō-par′tĭ-kĕl


  1. A very small particle, especially one that can pass through a filter of specified fineness.
  2. A vesicle, ranging in size from 5 to 100 mcm, released from the membrane of a cell into the circulation. Microparticles are immunologically unique to their cells of origin and may play a role in antigen presentation. Increased numbers of certain kinds of microparticle may be found in the circulation in vascular and thrombotic disorders.

[micro- + particle]