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varactor

[vuh-rak-ter]
noun
  1. a semiconductor diode whose capacitance changes to match applied voltage, used to tune circuits by varying the reactance.

Origin of varactor

1955–60; var(iable re)actor
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for varactor

varactor

noun
  1. a semiconductor diode that acts as a voltage-dependent capacitor, being operated with a reverse biasCompare varistor

Word Origin for varactor

C20: probably a blend of variable reactor
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