sensor

noun

sen·​sor ˈsen-ˌsȯr  ˈsen(t)-sər 

1

: a device that responds to a physical stimulus (such as heat, light, sound, pressure, magnetism, or a particular motion) and transmits a resulting impulse (as for measurement or operating a control)

2

: sense organ

Did you know?

Sensors are used today almost everywhere. Radar guns bounce microwaves off moving cars. A burglar alarm may use a photosensor to detect when a beam of light has been broken, or may use ultrasonic sound waves that bounce off moving objects. Still other sensors may detect pressure (barometers) or chemicals (Breathalyzers and smoke detectors). Stud finders, used by carpenters to locate wooden studs under a wall, may employ magnets or radar. Wired gloves, which relay information about the position of the fingers, are used in virtual-reality environments. A cheap car alarm may be nothing but a shock sensor, in which a strong vibration will cause two metal surfaces to come together.

Synonyms

• detector

Examples of sensor in a Sentence

Image sensors are used in digital cameras.

Infrared sensors can track an object's movement.

Recent Examples on the Web

The test was designed to simulate real traffic conditions with engineers embedding a series of sensors along the bridge to monitor stress, vibration and any deflection in the structure. —James Bickerton, MSNBC Newsweek, 25 Sep. 2025

The womb is a largely sterile environment, and once gestation involves external tubing, sensors, and ports, every interface becomes a potential entry point for microbes. —Kaif Shaikh, Interesting Engineering, 25 Sep. 2025

In the iPhone 16, this secondary sensor was still just 12 MP. —ArsTechnica, 25 Sep. 2025

This new quantum sensor uses individual atoms, cooled to just shy of absolute zero, to serve as targets for stray particles to hit. —IEEE Spectrum, 24 Sep. 2025

Word History

Etymology

Latin sentire to perceive + English -or entry 1 — more at sense

First Known Use

circa 1928, in the meaning defined at sense 1

Rhymes for sensor

• censer
• censor
• denser
• fencer
• tensor
• biosensor
• condenser
• dispenser
• extensor

Kids Definition

sensor

noun

sen·​sor ˈsen-ˌsȯ(ə)r 

ˈsen(t)-sər

: a device that detects a physical quantity (as a movement or a beam of light) and responds by transmitting a signal

Medical Definition

sensor

noun

sen·​sor ˈsen-ˌsȯ(ə)r  ˈsen(t)-sər 

: a device that responds to a physical stimulus (as heat, light, sound, pressure, magnetism, or a particular motion) and transmits a resulting impulse (as for measurement or operating a control)

also : sense organ