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definitions

closed source

noun

  1. intellectual property, esp computer source code, that is not made available to the general public by its creators
  2. (as modifier)closed source software Compare open source
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