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 of sensor

• 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

While heart rate and heart rate variability are part of the back-end algorithm, the sensors were also designed after studying the results of over 100 women wearing Peri. —Alexa Mikhail, Flow Space, 13 Nov. 2025

The report produced by Stefano Schiavon, a University of California-Berkeley professor who specializes in architectural engineering, thermal comfort and heat, relied on 31 sensors placed throughout the prison. —Ashley Miznazi, Miami Herald, 13 Nov. 2025

Multiple Omen units will share sensor data, coordinate flight paths, and adjust behavior in real time. —Aamir Khollam, Interesting Engineering, 13 Nov. 2025

Each tag had motion sensors, a camera with a light, hydrophones to pick up echolocation clicks, and GPS. —Laura Baisas, Popular Science, 13 Nov. 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