coarctation
    n 1: tight or narrow compression [syn: constriction,
         coarctation]
    2: (biology) a narrowing or constriction of a vessel or canal;
       especially a congenital narrowing of the aorta

Coarctation \Co`arc*ta"tion\, n. [L. coarctatio.]
   1. Confinement to a narrow space. [Obs.] --Bacon.
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   2. Pressure; that which presses. [Obs.] --Ray.
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   3. (Med.) A stricture or narrowing, as of a canal, cavity, or
      orifice.
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