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megohm

American  
[meg-ohm] / ˈmɛgˌoʊm /

noun

Electricity.
  1. a unit of resistance, equal to one million ohms. MΩ; meg


megohm British  
/ ˈmɛɡˌəʊm /

noun

  1.  .  one million ohms

"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 megohm

First recorded in 1865–70; meg- ( def. ) + ohm