circulation
    n 1: the dissemination of copies of periodicals (as newspapers
         or magazines)
    2: movement through a circuit; especially the movement of blood
       through the heart and blood vessels
    3: (library science) the count of books that are loaned by a
       library over a specified period
    4: number of copies of a newspaper or magazine that are sold;
       "by increasing its circulation the newspaper hoped to
       increase its advertising"
    5: free movement or passage (as of cytoplasm within a cell or
       sap through a plant); "ocean circulation is an important part
       of global climate"; "a fan aids air circulation"
    6: the spread or transmission of something (as news or money) to
       a wider group or area

Circulation \Cir`cu*la"tion\, n. [L. circulatio: cf. F.
   circulation.]
   1. The act of moving in a circle, or in a course which brings
      the moving body to the place where its motion began.
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            This continual circulation of human things. --Swift.
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   2. The act of passing from place to place or person to
      person; free diffusion; transmission.
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            The true doctrines of astronomy appear to have had
            some popular circulation.             --Whewell.
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   3. Currency; circulating coin; notes, bills, etc., current
      for coin.
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   4. The extent to which anything circulates or is circulated;
      the measure of diffusion; as, the circulation of a
      newspaper.
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   5. (Physiol.) The movement of the blood in the blood-vascular
      system, by which it is brought into close relations with
      almost every living elementary constituent. Also, the
      movement of the sap in the vessels and tissues of plants.
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