Meaning of IMPEDANCE in English

IMPEDANCE

[im.ped.ance] n (1886): something that impedes: hindrance: as a: the apparent opposition in an electrical circuit to the flow of an alternating current that is analogous to the actual electrical resistance to a direct current and that is the ratio of effective electromotive force to the effective current b: the ratio of the pressure to the volume displacement at a given surface in a sound-transmitting medium

Merriam-Webster English vocab.      Английский словарь Merriam Webster.