Transformer

noun
1.
a person or thing that transforms.
2.
Electricity. an electric device consisting essentially of two or more windings wound on the same core, which by electromagnetic induction transforms electric energy from one set of one or more circuits to another set of one or more circuits such that the frequency of the energy remains unchanged while the voltage and current usually change.
noun
1.
a device that transfers an alternating current from one circuit to one or more other circuits, usually with an increase (step-up transformer) or decrease (step-down transformer) of voltage. The input current is fed to a primary winding, the output being taken from a secondary winding or windings inductively linked to the primary
2.
a person or thing that transforms
transformer
(trāns-fôr’mər)

A device used to change the voltage of an alternating current in one circuit to a different voltage in a second circuit, or to partially isolate two circuits from each other. Transformers consist of two or more coils of conducting material, such as wire, wrapped around a core (often made of iron). The magnetic field produced by an alternating current in one coil induces a similar current in the other coils. ◇ If there are fewer turns on the coil that carries the source of the power than there are on a second coil, the second coil will provide the same power but at a higher voltage. This is called a step-up transformer. ◇ If there are fewer turns on the second coil than on the source coil, the outgoing power will have a lower voltage. This is called a step-down transformer. Compare converter, rectifier.

transformer definition

A device used to transfer electrical energy from one circuit to another. With an alternating current, a transformer will either raise or lower the voltage as it makes the transfer.