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reluctivity

American  
[rel-uhk-tiv-i-tee] / ˌrɛl əkˈtɪv ɪ ti /

noun

Electricity.
  1. the tendency of a magnetic circuit to conduct magnetic flux, equal to the reciprocal of the permeability of the circuit.


reluctivity British  
/ ˌrɛlʌkˈtɪvɪtɪ /

noun

  1. physics a specific or relative reluctance of a magnetic material

"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 reluctivity

First recorded in 1885–90; reluct + -ive + -ity