transformer

n. device for changing the voltage of electrical current

A transformer is a device that transfers electrical energy from one circuit to another through inductively coupled wires. A changing current in the first circuit (the primary) creates a changing magnetic field; in turn, this magnetic field induces a changing voltage in the second circuit (the secondary). By adding a load to the secondary circuit, one can make current flow in the transformer, thus transferring energy from one circuit to the other.
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Transformer, n an electrical device that increases or reduces the voltage of an alternating current by mutual induction between primary and [more]Transformer - Community and Resources

Noun
1. an electrical device by which alternating current of one voltage is changed to another voltage
(hypernym) electrical device
(hyponym) coil
(part-meronym) induction coil
(derivation) transform

v. change, modify, alter; convert, transform, metamorphose; work, process, make