Learner's definition of CIRCULATION
1 a : the movement of blood through the body that is caused by the pumping action of the heart b : movement of air, water, etc., through the different parts of something
The attic has poor air circulation.
the circulation of ocean waters
Let's open the windows to get some circulation in here.
2 [noncount] : the act of passing something (such as money, information, etc.) from person to person or place to place: the state of being passed from person to person or place to place
The coins have recently entered circulation.
That rumor has been in circulation [=has been going around] for a long time.
The magazine has been taken out of circulation. [=the magazine will no longer be made and sold]
3 [noncount] : the state of being actively involved in social activities (such as parties or dates)
She's finally getting back in/into circulation after her divorce. [=she has started dating and going out again after her divorce]
He'll be out of circulation [=unable to go out socially] for a while after the surgery.
4 [count] : the average number of copies of a newspaper, magazine, etc., that are sold over a particular period
The newspaper has the largest circulation in the country.
The magazine has a weekly circulation of about 70,000 subscribers nationwide.