A substance that has no resistance to conducting an electric current(noun)
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Use "superconductor" in a sentence
"The superconductor is described by a complex function called the order parameter, and indicates the fraction of electrons that has condensed into a superfluid."
"A superconductor is a material which has no electrical resistance whatever."
"The superconductor is the coil and not the air (assuming there is no core)."