mon·​i·​tor | \ ˈmä-nə-tər How to pronounce monitor (audio) \

Definition of monitor

 (Entry 1 of 2)

1a : a student appointed to assist a teacher
b : one that warns or instructs monitors and instructors for troops green in the art of warNew York Times
c : one that monitors or is used in monitoring: such as
(1) : an electronic device with a screen used for display (as of television pictures or computer information)
(2) : a device for observing a biological condition or function a heart monitor
3 [Monitor, first ship of the type]
a : a heavily armored warship formerly used in coastal operations having a very low freeboard and one or more revolving gun turrets
b : a small modern warship with shallow draft (see draft entry 1 sense 8) for coastal bombardment
4 : a raised central portion of a roof having low windows or louvers for providing light and air


monitored; monitoring\ ˈmä-​nə-​t(ə-​)riŋ How to pronounce monitor (audio) \

Definition of monitor (Entry 2 of 2)

transitive verb

: to watch, keep track of, or check usually for a special purpose Nurses monitored the patient's heart rate.

Other Words from monitor


monitorial \ ˌmä-​nə-​ˈtȯr-​ē-​əl How to pronounce monitor (audio) \ adjective
monitorship \ ˈmä-​nə-​tər-​ˌship How to pronounce monitor (audio) \ noun

Synonyms for monitor

Synonyms: Verb

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Examples of monitor in a Sentence

Noun They watched the press conference on a video monitor in a back room. We put a baby monitor in the nursery. U.N. weapons monitors and inspectors. Verb Nurses constantly monitored the patient's heart rate. We're in a good position to monitor and respond to customer concerns. Government agents have been monitoring the enemy's radio communications. See More
Recent Examples on the Web: Noun Starting today, Luna users can sign in with their profiles and play games directly through their TV or monitor. Kris Holt, Forbes, 3 Aug. 2022 Other features include scoring logs, stats, a heart rate monitor and step counter, and a battery that last up to two full rounds. John Thompson, Men's Health, 6 June 2022 Most people had a desktop computer, a monitor, and maybe a printer—but add to those external drives, scanners, wireless routers, and other peripheral devices, and those two standard outlets most of us had were simply overwhelmed. Bradley Ford, Popular Mechanics, 28 June 2022 Curtis’s view of the Foley stage is blocked by a vast computer monitor, an intentional obstruction: seeing how a sound is created would spoil his ability to evaluate its accuracy and effectiveness. Anna Wiener, The New Yorker, 27 June 2022 About 79% of companies use badge swipes to track office utilization data, 46% monitor Wi-Fi connections, and 26% use desk or room sensors, according to CBRE data. Aman Kidwai, Fortune, 27 June 2022 This has now been signed off on by the judge, the monitor, the attorney general. Paige Fry, Chicago Tribune, 21 June 2022 This sit/stand desktop riser is 37 inches wide and features two tiers that can hold a laptop, keyboard, mouse, second monitor, speakers and other office accessories. Nicole Charky-chami, The Hollywood Reporter, 9 June 2022 Alongside the new laptop models, LG is introducing the +view for LG Gram portable 16-inch monitor (16MQ70). Matthew Humphries, PCMAG, 7 June 2022 Recent Examples on the Web: Verb Wastewater tests, which monitor sewage for traces of COVID, reveal record-high levels of the virus in the U.S. Grady Mcgregor, Fortune, 27 July 2022 The closures schedule is subject to change depending on the weather, so residents are encouraged to monitor the Caltrans Quick Map for the most up-to-date traffic information. Itzel Luna, Los Angeles Times, 18 July 2022 Indiana continues to monitor for white-nose syndrome, and the research is in part funded through the Indiana Nongame Wildlife Fund. Karl Schneider, The Indianapolis Star, 5 July 2022 While urine tests are taken routinely during pregnancy to monitor for conditions like diabetes, dehydration or preeclampsia, women may not know that they can also be used to screen for drugs. Anne Branigin, Washington Post, 2 July 2022 This increase in salary cap also bumps the luxury tax line to over $150 million and the hard cap to nearly $157 million, which will be something to monitor for Chicago. Jason Patt, Forbes, 30 June 2022 The city will continue working with Scripps, the state Parks Department and the California Coastal Commission to monitor the bluff for signs of another slide. Phil Diehl, San Diego Union-Tribune, 30 June 2022 Westlake will also install monitors around the boundary of each facility to monitor for benzene, a potent carcinogen. Lisa Song, ProPublica, 29 June 2022 Visitors should monitor Yellowstone's website and social media for more updates, the park said. Bu Holly Yan And Raza Razek, CNN, 19 June 2022 See More

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

First Known Use of monitor


1530, in the meaning defined at sense 1a


1924, in the meaning defined above

History and Etymology for monitor

Noun and Verb

Latin, one that warns, overseer, from monēre to warn — more at mind

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Time Traveler for monitor

Time Traveler

The first known use of monitor was in 1530

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Dictionary Entries Near monitor



monitor bug

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Statistics for monitor

Last Updated

9 Aug 2022

Cite this Entry

“Monitor.” Dictionary, Merriam-Webster, Accessed 9 Aug. 2022.

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More Definitions for monitor


mon·​i·​tor | \ ˈmä-nə-tər How to pronounce monitor (audio) \

Kids Definition of monitor

 (Entry 1 of 2)

1 : a video screen used for display (as of television pictures or computer information)
2 : a student in a school picked for a special duty (as keeping order)
3 : a person or thing that watches or checks something a heart monitor


monitored; monitoring

Kids Definition of monitor (Entry 2 of 2)

: to watch or check for a special reason Nurses monitored the patient's heart rate.


mon·​i·​tor | \ ˈmän-ət-ər How to pronounce monitor (audio) \

Medical Definition of monitor

 (Entry 1 of 2)

: one that monitors especially : a device for observing or measuring a biologically important condition or function a heart monitor


transitive verb
monitored; monitoring\ ˈmän-​ət-​ə-​riŋ, ˈmän-​ə-​triŋ How to pronounce monitor (audio) \

Medical Definition of monitor (Entry 2 of 2)

1 : to watch, observe, or check closely or continuously monitor a patient's vital signs
2 : to test for intensity of radiations especially if due to radioactivity

More from Merriam-Webster on monitor

Nglish: Translation of monitor for Spanish Speakers

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


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