(noun.) the spread or transmission of something (as news or money) to a wider group or area.
(noun.) the dissemination of copies of periodicals (as newspapers or magazines).
(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'.
(noun.) movement through a circuit; especially the movement of blood through the heart and blood vessels.
(noun.) number of copies of a newspaper or magazine that are sold; 'by increasing its circulation the newspaper hoped to increase its advertising'.
(noun.) (library science) the count of books that are loaned by a library over a specified period.
达斯汀录入
校对:杜鲁门