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De Forest

[di fawr-ist, for-]
noun
  1. Lee,1873–1961, U.S. inventor of radio, telegraphic, and telephonic equipment.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for de forest

De Forest

noun
  1. Lee. 1873–1961, US inventor of telegraphic, telephonic, and radio equipment: patented the first triode valve (1907)
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