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

The system understands the space around the user via computer vision sensors (cameras recognize objects, surfaces, gestures); lidars accurately measure distances and build a 3D map of space; special sensors determine the shape and volume of objects. —Connie Etemadi, USA Today, 23 Mar. 2026

According to Army Recognition, the new tanks and sensor pods align with ongoing upgrades, such as the Infrared Defensive System, based on TacIRST technology, designed to improve the aircraft’s survivability and target-detection capabilities. —Kaif Shaikh, Interesting Engineering, 23 Mar. 2026

However, a stray thermal vibration can scramble qubit states in quantum computing or degrade the coherence in quantum sensors. —Etiido Uko march 23, New Atlas, 23 Mar. 2026

The device, a compact high-explosive limpet mine designed to rest along the seabed, relies on a combination of acoustic and three-axis magnetic sensors to detect nearby vessels. —James Laporta, CBS News, 23 Mar. 2026

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