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warchalking

noun
  1. the practice of marking chalk symbols on walls and pavements at places where local wireless internet connections may be obtained for free via a computer, usually without permission
Derived Formswarchalker, noun

Word Origin for warchalking

C21: from w(ireless) a(cess) r(evolution) + gerund of chalk
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