circulation of blood between the embryo and the yolk sac | the spread or transmission of something (as news or money) to a wider group or area |
| the dissemination of copies of periodicals (as newspapers or magazines) |
| free movement or passage (as of cytoplasm within a cell or sap through a plant) |
| movement through a circuit; especially the movement of blood through the heart and blood vessels |
| number of copies of a newspaper or magazine that are sold |
| (library science) the count of books that are loaned by a library over a specified period |