The circulation of a newspaper or magazine is the number of copies that are sold each time it is produced.

Your circulation is the movement of blood through your body.

If something such as money is in circulation, it is being used by the public. If something is out of circulation or has been withdrawn from circulation, it is no longer available for use by the public.

If someone is out of circulation, they do not appear in public or at social gatherings for a period of time. You can also say that someone is out of circulation when they are in prison.