impedance

noun

1. a material's opposition to the flow of electric current; measured in ohms

   noun.phenomenon

   Synonyms electric resistance electrical resistance ohmic resistance resistance resistivity

   Source: WordNet 3.0

2. 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 <i>R² + X²</i>, where <i>R</i> = ohmic resistance, <i>X</i> = reactance. For an inductive circuit, <i>X = 2&pi;fL</i>, where <i>f</i> = frequency and <i>L</i> = self-inductance; for a circuit with capacity <i>X = 1 &divide; 2&pi;fC</i>, where <i>C</i> = capacity.

   noun

   Source: webster1913