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Thompson sub-machine-gun

noun
  1. trademark a .45 calibre sub-machine-gunAlso called: Tommy gun

Word Origin for Thompson sub-machine-gun

C20: after John T. Thompson (1860–1940), US Army Officer, its coinventor
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