What is a concussion or shock produced by a blow or other injury, in a part or region opposite to that at which the blow is received, often causing rupture or disorganisation of the parts affected called?

contrecoup — A concussion or shock produced by a blow or other injury, in a part or region opposite to that at which the blow is received, often causing rupture or disorganisation of the parts affected. (Webster's 1913.)

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