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Aldis lamp

noun
  1. a portable lamp used to transmit Morse code

Word Origin for Aldis lamp

C20: originally a trademark, after A. C. W. Aldis, its inventor
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