sen·​sor | \ ˈsen-ˌsȯr How to pronounce sensor (audio) , ˈsen(t)-sər\

Definition of sensor

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)

Keep scrolling for more

Synonyms for sensor



Visit the Thesaurus for More 

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.

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

When Lion Air Flight 610 crashed, killing 189 people last October, pilots frantically looked through a handbook, searching for a way to override the plane's automatic aircraft nose down feature, triggered by inaccurate sensor readings. Eric Limer, Popular Mechanics, "Lion Air Pilots Had Less Than a Minute to Avert Fatal Crash," 27 Mar. 2019 Understory has deployed some 500 weather sensors across the U.S. Sarah Hauer, Milwaukee Journal Sentinel, "Company tracking weather at ground level is named one of the most innovative agtech startups," 12 July 2018 Earlier this month, Google notified users that Nest Guard (the alarm, keypad and motion-sensor component of Nest Home Secure) was now compatible with the company's Home Assistant voice-control function. Sam Blum, Popular Mechanics, "Google Calls Hidden Microphone in Its Nest Home Security Devices an 'Error'," 21 Feb. 2019 The other exciting new releases are the Smart Switch, which has motion sensors built into it, and new smart accessories like a special wall plug. Hadley Mendelsohn, House Beautiful, "General Electric Is Making Voice-Controlled "Smart" Light Bulbs," 9 Jan. 2019 For one, the indoor drone is designed with motion sensors, so kids can fly it around and perform tricks with just their hands — no remote needed! Lindsey Murray, Good Housekeeping, "Air Hogs Supernova Is the Hottest "Big Kid Toy" of 2018," 1 Nov. 2018 The Gravesend Inn Haunted Hotel, which has been running annually for 20 years, is built and operated by students at City Tech, who help work the complicated system of animatronic characters and motion sensors that trigger special effects. Rebecca Jennings, Vox, "The Halloween experience in 2018 is less spooky and more selfies.," 22 Oct. 2018 Another feature, called RideCheck, uses motion sensors and GPS in both the riders’ and drivers’ phones to detect if your Uber car has crashed. Johana Bhuiyan, Recode, "Uber’s sleek new product? Your safety.," 6 Sep. 2018 The Andaz Maui at Wailea Resort has sustainable elements that include a solar hot water system, variable speed chillers, LED lighting, motion-sensor lighting controls and low-flow plumbing fixtures. Jill K. Robinson,, "Going green: Can we travel the world without killing the planet?," 21 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'sensor.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

See More

First Known Use of sensor

circa 1928, in the meaning defined at sense 1

History and Etymology for sensor

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

Keep scrolling for more

Learn More about sensor

Statistics for sensor

Last Updated

17 Apr 2019

Look-up Popularity

Time Traveler for sensor

The first known use of sensor was circa 1928

See more words from the same year

Keep scrolling for more

More Definitions for sensor



English Language Learners Definition of sensor

: a device that detects or senses heat, light, sound, motion, etc., and then reacts to it in a particular way


sen·​sor | \ ˈsen-ˌsȯ(ə)r How to pronounce sensor (audio) , ˈsen(t)-sər How to pronounce sensor (audio) \

Medical Definition of sensor

: 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

Keep scrolling for more

More from Merriam-Webster on sensor

Rhyming Dictionary: Words that rhyme with sensor

Thesaurus: All synonyms and antonyms for sensor

Spanish Central: Translation of sensor

Nglish: Translation of sensor for Spanish Speakers

Britannica English: Translation of sensor for Arabic Speakers Encyclopedia article about sensor

Comments on sensor

What made you want to look up sensor? Please tell us where you read or heard it (including the quote, if possible).


marked by a state of overwhelming emotion

Get Word of the Day daily email!

Test Your Vocabulary

Words from Greek and Latin Quiz

  • roman forum
  • Which of the following months comes from a Latin word for “ten”?
True or False

Test your knowledge - and maybe learn something along the way.

Bee Cubed

Test Your Knowledge - and learn some interesting things along the way.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!