Main Entry: im·ped·ance

Pronunciation: \im-ˈpē-d^ən(t)s\

Function: noun

Date: 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