kidney-punch

Noun

kidney punch (plural kidney punches)

1. A blow struck with the fist to the lower back region, capable of causing serious internal injury and not permitted under the rules of boxing.
   • Following the bout, Schmeling said he was fouled. He said that he was hit a kidney punch, a devastating right, which so shocked his nervous system that he was dazed and his vision was blurred1938 June 22, James P. Dawson, “Fight, Might and Whata Right!”, in New York Times, retrieved 06 Jan 2014

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