sen·sor | \ ˈsen-ˌsȯr , 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)

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Synonyms for sensor



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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

But the cameras were foiled by high prices, a one-inch sensor that was smaller than those used by the competition, and a confusing naming scheme. Chris Welch, The Verge, "Nikon discontinues its Nikon 1 lineup of mirrorless cameras," 11 July 2018 If a sensor detects motion, the Internet hub will send a push notification through the app. Necee Regis,, "A new Nantucket hotel, Cayman Islands refunds, and other tidbits," 26 June 2018 In April, a group of eighth graders received a top prize in Samsung’s Solve for Tomorrow national competition for the design of a football helmet with a sensor that can detect concussions. Julie Lasky, New York Times, "Upper Saddle River, N.J.: Quiet and Neat as a Pin," 20 June 2018 Instead of relying on visual input from a camera or other sort of sensor system, the Cheetah 3 is designed to be able to feel its way around the environment, which could make uniquely suited to traverse unpredictable and/or pitch black spaces. Eric Limer, Popular Mechanics, "MIT's Cheetah 3 Has a Precision Pounce," 5 July 2018 With the new sensors, the project is expected to cover a larger area — outside of San Ysidro — including nearby regions of Otay Mesa and the eastern edge of Imperial Beach. David Hernandez,, "State funds to expand San Ysidro air quality project," 5 July 2018 To fix Apple Maps, the report said that the company outfitted a squad of vans with sensors and sent them to collect updated mapping data in a number of cities. Jonathan Vanian, Fortune, "Apple Maps Is Undergoing a Major Overhaul to Improve Its Accuracy," 29 June 2018 Railroads across the country are complying with a mandate to install Positive Train Control, a computerized system operated with sensors that will stop a train if an engineer can’t. Carole Carlson, Post-Tribune, "South Shore fare hike takes effect Sunday," 28 June 2018 Here’s what truckers on I-4 had to say about the sensor system last October. Martin E. Comas,, "New sensors alert truckers to open spaces on I-4 rest area in Seminole, others on I-95," 27 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.

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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

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Statistics for sensor

Last Updated

18 Sep 2018

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Time Traveler for sensor

The first known use of sensor was circa 1928

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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 , ˈsen(t)-sər \

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

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