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