transformer

American  

[trans-fawr-mer] / trænsˈfɔr mər /

noun

1. a person or thing that causes or undergoes a change in appearance, structure, character, etc.

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.

3. Computers. Also transformer model a type of neural network that uses statistical relationships between sequential data, such as words and sentences, to learn context and produce output.

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transformer British  

/ trænsˈfɔːmə /

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

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transformer Scientific  

/ trăns-fôr′mər /

1. 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.

2. ◆ 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.

3. ◆ 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.

4. Compare converter rectifier

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transformer Cultural  

1. 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.

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Etymology

Origin of transformer

First recorded in 1595–1605; transform + -er ¹

Example Sentences

He said he was trying to block Edison’s crew from burying a large transformer between two towering deodar cedar trees.

From Los Angeles Times • Feb. 17, 2026

Backers include Lukasz Kaiser, one of eight Google researchers who kicked off the transformer era in 2017 with the paper “Attention Is All You Need,” and early-stage investor TQ Ventures.

From The Wall Street Journal • Dec. 1, 2025

Authorities in Mexico said on Saturday that a faulty electric transformer may have caused an explosion that killed at least 23 people in a supermarket.

From Barron's • Nov. 2, 2025

The prosecutor's office in the northern state of Sonora said in a statement that "the working assumption is that the incident was accidental, and the investigation is looking into a transformer located inside the store."

From Barron's • Nov. 2, 2025

Alighting on the corrected transformer pole, she waited for Susan to appear with food.

From "Frightful's Mountain" by Jean Craighead George

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