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

Scientists at the University of Washington have equipped bumblebees with tiny sensors that could one day be used to monitor crops on a farm. Katherine Long, The Seattle Times, "Backpack-wearing bumblebees could buzz fields, tell farmers how crops are doing," 13 Dec. 2018 With these sensors, the Ecobee4 can tell the conditions in different areas of your house and fine-tune temperature controls as needed. Alexandria Haslam, PCWorld, "The best smart thermostat you can buy, the Alexa-enabled Ecobee4, is $50 off," 16 Nov. 2018 Most of the barrier is a concrete wall topped by steel mesh, sensors and surveillance cameras. Fox News, "Israeli wall rising near border with Lebanon stokes tensions," 6 Sep. 2018 To achieve this, scientists have begun outfitting technology with the same sensors that human beings use. Bill Gourgey, WIRED, "How Artificial Intelligence Could Prevent Natural Disasters," 10 July 2018 This summer, a company called Virfit introduced the Vhoop fitted with sensors and a Bluetooth transmitter to monitor a user’s every twist and turn via smartphone app, marrying the quintessential 1950s obsession to the latest fitness-tracking fad. Alec Scott, Smithsonian, "The Iconic Hula Hoop Keeps on Rolling," 26 June 2018 Data are collected by special vehicles carrying sensors and cameras. Yuri Kageyama, The Christian Science Monitor, "Japan inches closer to ultra-precise 3-D maps for self-driving cars," 14 June 2018 SpaceX has been trying to get this launch off the ground for the last week, but a combination of bad weather and strange sensor readings on the rocket forced the company to push back the mission until Saturday, December 22nd. Loren Grush, The Verge, "Watch SpaceX launch its final Falcon 9 rocket of the year for the Air Force," 21 Dec. 2018 The Sunflowers—which are disguised as garden lights—also act as ground sensors and can detect motion. Brittney Morgan, House Beautiful, "Drones Might Just Be The Future Of Home Security," 7 Dec. 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

9 Jan 2019

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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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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).


to gather or build up little by little

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