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

Picture a power grid that heals itself, a warehouse that tracks every box without sensors, or a fleet of autonomous drones that defend themselves without phoning home. —Amir Husain, Forbes, 22 Mar. 2025

Trump’s planned Golden Dome missile defense shield, which could require hundreds of sensors and other satellites to keep watch for incoming ballistic missiles, would be a natural fit for SpaceX and its Starlink unit. —Nandita Bose, USA TODAY, 21 Mar. 2025

L3Harris leads development of a software system called ATLAS to manage data from a network of sensors tracking rocket launches and objects in orbit. —Ars Technica, 21 Mar. 2025

One of the most innovative additions is a set of sensors embedded in the nosepad: a PPG sensor for heart rate monitoring and a contact microphone to distinguish the wearer's voice from others. —Kurt Knutsson, Cyberguy Report, Fox News, 20 Mar. 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