ˌsərkyəˈlāshən, -ə̄k-, -əik- noun
( -s )
Etymology: Middle French or Latin; Middle French, from Latin circulation-, circulatio, from circulatus + -ion-, -io -ion
1. : movement or passage in a circuit or other curving or bending course typically with return to a starting point
circulation of air through the building
circulation of water in the lake
2. : the orderly movement of liquid or dissolved matter through a living body:
a. : the movement of blood through the vessels of the body that is induced by the pumping action of the heart and serves to distribute nutrients and oxygen to and remove waste products from all parts of the body; in man, other mammals, and birds being double, the blood making two distinct circuits and the arterial and venous blood being completely separated by capillary networks; in amphibians and reptiles the circuits being imperfect with some mixing of blood in the single ventricle; and in fishes, a single circuit occurring, the blood passing over the gills and thence to the tissues and back to the heart — see pulmonary circulation , systemic circulation
b. : analogous movement of fluid through defined channels and tissue spaces in the bodies of various invertebrates
c. : the flow of sap in a plant
3. obsolete : continuous repetition of actions in a set order
a daily circulation of sorrow — Daniel Defoe
4. : the act of circulating or being circulated : passage or transmission from person to person or place to place:
a. : popular dissemination : distribution : widespread transmission
the book had wide circulation and its first publication was followed by many successive editions — J.T.Howard
the report which was in general circulation within five minutes after his entrance — Jane Austen
b. : passage of money or other means of exchange from person to person throughout a group or society
calling in gold coins in circulation
: money so circulated : currency
the circulation was again so worn and clipped that the sixth recoinage followed — John Craig
5.
a. : the average number of copies of a publication sold or less freqently distributed over a given period
a country paper with little more than five hundred circulation — W.A.White
b. : the number of persons exposed to an advertisement or sales message by the use of a certain advertising medium ; especially : potential audience with available receiving sets
the circulation of a radio program
increasing TV circulation
6.
a. : the elements of communication within a building (as foyers, halls, corridors, stairways, and elevators)
b. : unhindered passage or motion about an area
this arrangement of doors permits easy circulation
a parking garage with free circulation of cars
7. : the line integral of a vector field around a closed curve
8.
a. : the lending of books or other library materials for outside use
b. : the total number of items taken by borrowers from a library
c. : a single borrowing of a library book
a strong binding good for 100 circulations
9. : free active social life with different persons or groups
getting back into circulation after her divorce