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pom

American  
[pom] / pɒm /

noun

(often initial capital letter)
  1. pommy.


POM 1 British  

abbreviation

  1. prescription-only medicine or medication Compare OTC

"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

pom 2 British  
/ pɒm /

noun

  1. slang  short for pommy

"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 pom

Probably by back formation