Definition of "impedance"

The act of impeding; that which impedes; a hindrance.  quotations  examples

(physics) A measure of the opposition to the flow of an alternating current in a circuit; the aggregation of its resistance, and inductive and capacitive reactances; the ratio of voltage to current treated as complex quantities.  examples

(physics) A quantity analogous to electrical impedance in some other energy domain

1. (physics, usually with “mechanical”) a measure of opposition to motion of something subjected to a force; the ratio of force to velocity treated as complex quantities.  examples

2. (physics, usually with “acoustic” or “sound”) the ratio of sound pressure to volume flow rate treated as complex quantities.  examples