coagulation cascade, the series of steps beginning with activation of the intrinsic or extrinsic pathways of coagulation and proceeding through the common pathway of coagulation to the formation of the fibrin clot. Each step involves activation of a proenzyme (zymogen), the activated form catalyzing activation of the following step. See also common pathway of coagulation, extrinsic pathway of coagulation, intrinsic pathway of coagulation.
