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definitions

par avion

[pa ra-vyawn]
adverb French.
  1. by plane (used especially as a designation on matter to be sent by airmail).
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for par avion

par avion

adverb
  1. by aeroplane: used in labelling mail sent by air
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