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GBZ

British  

abbreviation

  1. Gibraltar (international car registration)

"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

Etymology

Origin of GBZ

from G(reat) B(ritain) + Z (in place of G, which was already used in Guernsey )