any of a class of simple proteins that are soluble in ammonia, do not coagulate by heat, and yield relatively few amino acids upon hydrolysis: used to control hemorrhage
prot(o)- + amine
See protamine in American Heritage Dictionary 4
Any of a group of simple proteins found in fish sperm that are strongly basic, are soluble in water, are not coagulated by heat, and yield chiefly arginine upon hydrolysis. In purified form, they are used in a long-acting formulation of insulin and to neutralize the anticoagulant effects of heparin.