D defs.my
Entry 1 sense Webster, 1913

Impedance

/ĭmˌ-pēd'-əns/ · Im·ped·ance · IPA /[ɪmˈpidn̩s]/
01 n. The apparent resistance in an electric circuit to the flow of an alternating current, analogous to the actual electrical resistance to a di…
  1. 1.
    The apparent resistance in an electric circuit to the flow of an alternating current, analogous to the actual electrical resistance to a direct current, being the ratio of electromotive force to the current. It is equal to R2 + X2, where R = ohmic resistance, X = reactance. For an inductive circuit, X = 2πfL, where f = frequency and L = self-inductance; for a circuit with capacity X = 1 ÷ 2πfC, where C = capacity.(Elec.)