sensor

American  

[sen-sawr, -ser] / ˈsɛn sɔr, -sər /

noun

1. a mechanical device sensitive to light, temperature, radiation level, or the like, that transmits a signal to a measuring or control instrument.

2. a sense organ.

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sensor British  

/ ˈsɛnsə /

noun

1. anything, such as a photoelectric cell, that receives a signal or stimulus and responds to it

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Etymology

Origin of sensor

First recorded in 1925–30; sense + -or ²

Explanation

An electronic device that measures changes in a physical quality (like light or temperature) is a sensor. Your kitchen smoke alarm has a sensor that detects the smoky evidence of your badly burned toast. Sensors, these tiny gadgets that detect a physical property, note any changes in it, and convey a message about it electronically, are found just about everywhere. They detect the presence of carbon monoxide in your house, tell you what the temperature is, and help drivers back up safely, alerting them of any obstacles. Smartphones themselves contain many sensors — detecting vibration, tilt, magnetic fields, and more. Sensor comes from a Latin root meaning "perceive or feel."

Example Sentences

After splashdown, a separate Armstrong Flight Research Center team will collect a fortified sensor affixed to the exterior of the capsule that is designed to study the heat shield up close.

From Los Angeles Times • Apr. 9, 2026

He said another is sensor capability -- "the ability for us to know exactly where we are in space."

From Barron's • Apr. 4, 2026

“A carbon-monoxide sensor only monitors carbon monoxide. Any other gas, there is no reaction,” says Ainos’s Liu.

From The Wall Street Journal • Mar. 17, 2026

"It's the primary sensor that tells your brain when it's cold. We've known for a long time that this happens, but we didn't know how. Now we can see it."

From Science Daily • Mar. 8, 2026

He carried his photographs down a long hallway, went downstairs and through a security door, swiping his id card across a sensor, and entered a warren of rooms.

From "The Hot Zone" by Richard Preston