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retorsion

American  
[ri-tawr-shuhn] / rɪˈtɔr ʃən /
Or retortion

noun

International Law.
  1. retaliation or reprisal by one state identical or similar to an act by an offending state, such as high tariffs or discriminating duties.


retorsion British  
/ rɪˈtɔːʃən /

noun

  1. rare retaliatory action taken by a state whose citizens have been mistreated by a foreign power by treating the subjects of that power similarly; reprisal

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of retorsion

1650–60; < Medieval Latin retorsiōn- (stem of retorsiō, variant of retortiō ); see retortion