Circulation
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The English Wiktionary has a dictionary definition (meanings of a word) for: circulation
Circulation may be used in reference to:
- Circulatory system, a biological organ system whose primary function is to move substances to and from cells
- Circulation (fluid dynamics), the path integral of the fluid velocity around a closed curve
- Exhaust gas recirculation, a nitrogen oxide reduction technique
- Atmospheric circulation, the large-scale movement of air
- Newspaper circulation, the average number of copies of a newspaper distributed on a day
- Magazine circulation, the average number of copies of a periodical distributed per edition/ volume
- Library circulation, the activities around the lending of library books and other material to users of a lending library
- Circulation (currency), the transfer of currency through the hands of civilians