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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

Derived forms: circulations

Type of: airing, change of location, count, dissemination, organic phenomenon, public exposure, spread, spreading, travel

Encyclopedia: Circulation, American Heart Foundation