Definition of reluctivity in US English:

reluctivity

noun

Electricity Magnetism
  • One of the physical parameters of a magnetic material, equal to the reluctance per unit volume and equivalent to the reciprocal of magnetic permeability.

Origin

Late 19th century; earliest use found in Oliver Heaviside (1850–1925), physicist and electrical engineer. From reluct- + -ivity.

Pronunciation

reluctivity

/ˌriːlʌkˈtɪvɪti/