IMPEDANCE

n. total amount of resistance (Electricity, Physics); obstacle, hindrance

Impedance may refer to:the ratio of the voltage  phasor to the electric current phasor, as inElectrical impedance, a measure of opposition to time-varying electric current in an electric circuit.Characteristic impedance, a measure of opposition to electric current propagation in a transmission line.Impedance matching and Impedance mismatch.Vacuum impedance, a universal constant.Electromagnetic impedance, a constant related to electromagnetic wave propagation in a medium.Mechanical impedance, a measure of opposition to motion of a structure subjected to a force.Acoustic impedance, a constant related to the propagation of sound waves in an acoustic medium.Linear response function, a general way to represent the input-output characteristics of a system.
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Impedance /im·ped·ance/ obstruction or opposition to passage or flow, as of an electric current or other form of energy. Symbol Z. [more]Impedance - Community and Resources

Noun
1. a material's opposition to the flow of electric current; measured in ohms
(synonym) electric resistance, electrical resistance, resistance, resistivity, ohmic resistance
(hypernym) electrical phenomenon
(hyponym) ohmage

n. impedance, total amount of resistance (Electricity, Physics); obstacle, hindrance