resistor

American  

[ri-zis-ter] / rɪˈzɪs tər /

noun

Electricity.

1. a device designed to introduce resistance into an electric circuit.

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resistor British  

/ rɪˈzɪstə /

noun

1. an electrical component designed to introduce a known value of resistance into a circuit

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resistor Scientific  

/ rĭ-zĭs′tər /

1. A device used in electrical circuits to maintain a constant relation between current flow and voltage. Resistors are used to step up or lower the voltage at different points in a circuit and to transform a current signal into a voltage signal or vice versa, among other uses. The electrical behavior of a resistor obeys Ohm's law for a constant resistance; however, some resistors are sensitive to heat, light, or other variables.

2. ◆ Variable resistors, or rheostats, have a resistance that may be varied across a certain range, usually by means of a mechanical device that alters the position of one terminal of the resistor along a strip of resistant material. The length of the intervening material determines the resistance. Mechanical variable resistors are also called potentiometers, and are used in the volume knobs of audio equipment and in many other devices.

3. Compare capacitor See more at Ohm's law

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Etymology

Origin of resistor

First recorded in 1900–05; resist + -or ²

Example Sentences

Once in the late 1950s, while building machinery to record sounds a heart makes, he accidentally used the wrong resistor, but its electrical pulse rate was steady, like a heartbeat.

From The Wall Street Journal • Apr. 4, 2026

Currently, the memory resistor, or "memristor," is the most well-developed technology that can perform combined processing and memory function.

From Science Daily • Dec. 21, 2023

A temperature-dependent resistor, or thermistor, senses the temperature, which controls the smell’s intensity.

From Scientific American • May 9, 2023

The business, then called Kyoto Ceramic Company, got its first big break when it received an order to make resistor rods for the Apollo space program.

From New York Times • Sep. 2, 2022

Maybe it’s wax dripping from the condenser or charcoal built up on a resistor.

From "All the Light We Cannot See" by Anthony Doerr