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n. A protein in the blood plasma that is essential for the coagulation of blood and is converted to fibrin by the action of thrombin in the presence of ionized calcium.

n. A protein that in humans plays a part in the forming of clots.

n. An albuminous substance existing in the blood, and in other animal fluids, which either alone or with fibrinoplastin or paraglobulin forms fibrin, and thus causes coagulation.

n. A proteid substance belonging to the group of globulins, found in the blood and concerned in the process of coagulation.

n. a protein present in blood plasma; converts to fibrin when blood clots

"The Framingham study that has led to most of the theories about cholesterol levels and heart disease risk has now produced some interesting facts about another risk factor, the blood level of a blood-clotting factor called fibrinogen."

clotting factor    coagulation factor