circulation

/ˈsʌrkjəˌleɪʃən/

/səkjəˈleɪʃɪn/

Other forms: circulations

The word circulation refers to the movement of blood through your body's blood vessels and heart. It can also mean free movement in a more general sense, as in the circulation of news, money, or even library books.

Circulation of blood is what happens in your body's circulatory system. There are other kinds of circulation too, like sap moving through a plant, air moving freely within a building, or even party guests strolling around your living room. The key thing they all have in common is orderly movement. The Latin root, circulare, means "to form a circle."

Definitions of circulation

1. noun

   movement through a circuit; especially the movement of blood through the heart and blood vessels
   types:

   systemic circulation

   circulation that supplies blood to all the body except to the lungs

   pulmonary circulation

   circulation of blood between the heart and the lungs

   vitelline circulation

   circulation of blood between the embryo and the yolk sac

   type of:

   organic phenomenon

   (biology) a natural phenomenon involving living plants and animals
2. noun

   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”

   type of:

   change of location, travel

   a movement through space that changes the location of something
3. noun

   the spread or transmission of something (as news or money) to a wider group or area
   types:

   recirculation

   circulation again

   type of:

   spread, spreading

   act of extending over a wider scope or expanse of space or time
4. noun

   the dissemination of copies of periodicals (as newspapers or magazines)
   type of:

   airing, dissemination, public exposure, spreading

   the opening of a subject to widespread discussion and debate
5. noun

   number of copies of a newspaper or magazine that are sold
   “by increasing its circulation the newspaper hoped to increase its advertising”

   type of:

   count

   the total number counted
6. noun

   (library science) the count of books that are loaned by a library over a specified period
   type of:

   count

   the total number counted