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par avion

American  
[pa ra-vyawn] / pa raˈvyɔ̃ /

adverb

French.
  1. by plane (used especially as a designation on matter to be sent by airmail).


par avion British  
/ par avjɔ̃ /

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