What is the science or art of signs. Specifically: (a) (Med.) The science of the signs or symptoms of disease; symptomatology. (b) The art of using signs in signaling called?

semeiology — The science or art of signs. Specifically: (a) (Med.) The science of the signs or symptoms of disease; symptomatology. (b) The art of using signs in signaling. (Webster's 1913.)

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