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balun

American  
[bal-uhn] / ˈbæl ən /

noun

Electricity.
  1. a device for converting a balanced line into an unbalanced line and vice versa.


balun British  
/ ˈbælən /

noun

  1. electronics a device for coupling two electrical circuit elements, such as an aerial and its feeder cable, where one is balanced and the other is unbalanced

"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 balun

bal(ance) + un(balance)