\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.
         This continual circulation of human things. --Swift.
2. The act of passing from place to place or person to
   person; free diffusion; transmission.
         The true doctrines of astronomy appear to have had
         some popular circulation.             --Whewell.
3. Currency; circulating coin; notes, bills, etc., current
   for coin.
4. The extent to which anything circulates or is circulated;
   the measure of diffusion; as, the circulation of a
   newspaper.
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.