circulatory system UK /ˌsɜːk(j)uːlətəɹi ˈsɪstəm/US /ˌsɝkjələˌtɔɹi ˈsɪstəm/ noun2 •The parts of an animal body comprising the heart, blood vessels (arteries, veins, and capillaries), and blood, which circulate the blood around the body. •The parts of a machine responsible for the circulation of some fluid. formscirculatory systems
