What is 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 called?

fibrinogen — 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. (Webster's 1913.)

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