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 monitoring (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.

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Other Words from monitor


monitorial \ ˌmä-​nə-​ˈtȯr-​ē-​əl How to pronounce monitorial (audio) \ adjective
monitorship \ ˈmä-​nə-​tər-​ˌship How to pronounce monitorship (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.
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Recent Examples on the Web: Noun In any case, the difference is fairly stark: A USB-C hub can power an external 4K monitor at an eye-straining 30Hz, but a Thunderbolt 3 dock has enough typical bandwidth to power a pair of 4K displays at a more comfortable 60Hz refresh rate. Mark Hachman, PCWorld, "The Belkin Thunderbolt Dock Core is the first dual-powered Thunderbolt dock," 29 June 2020 For tele-working families, Morgan could set up dual-monitor screens and show clients how their children could use iPads for homeschooling. Lacrai Mitchell, CBS News, "Black North Carolina business owners adapt to financial uncertainty amid pandemic," 25 June 2020 Using a command line, admins can manage user machines, initiate and configure antivirus scans, monitor network events, and manage various threats. Dan Goodin, Ars Technica, "Microsoft is adding Linux, Android, and firmware protections to Windows," 23 June 2020 Cox wears a continuous glucose monitor (CGM) on her arm and an insulin pump (that connects via tube to an infusion port in her hip) to manage her levels. Akeem Glaspie, The Indianapolis Star, "Fever rookie Lauren Cox: Competitor, inspiration, ready to return basketball," 21 June 2020 Two weeks earlier her 30-year-old daughter, whose name this news organization is protecting at Bearden’s request, was assigned a new job as an inmate monitor working the 2 p.m. to 10 p.m. shift. Jo Ciavaglia, USA TODAY, "Lower Makefield family fights for info, treatment for mentally ill daughter in Bucks jail," 20 June 2020 These capture the class M50 studio-monitor design but add modern comforts like bluetooth, button controls for microphone and song selection, and a voice assistant. Popular Science, "Over-the-ear headphones to immerse you in high-quality sound," 19 June 2020 The independent monitor in Denver, Colorado, which was created in 2004, has all of those powers. Victor Luckerson, The New Yorker, "Tulsa’s Hopeful Anger," 16 June 2020 LA County advised its residents to quarantine for two weeks and monitor symptoms, per the advice of LA Department of Public Health. Leah Asmelash, CNN, "Protesters should self-quarantine for two weeks, LA County says," 10 June 2020 Recent Examples on the Web: Verb The county health department in a news release said anyone who was at Fifth Avenue Friday, June 19, should monitor themselves for signs and symptoms of COVID-19 because of potential exposure to the virus. Susan Selasky, Detroit Free Press, "3 people test positive for coronavirus after visiting Fifth Avenue bar in Royal Oak," 30 June 2020 Teachers will monitor students, and if symptoms are present, will refer them to the nurse to be sent home. Brandi Addison, Dallas News, "Frisco ISD asking parents to commit students to in-person or online learning for 2020-21 school year," 29 June 2020 The team will monitor the state’s COVID-19 effective rate of reproduction using information from the CDC, World Health Organization, Alabama Department of Public Health, and Bama Tracker. al, "Pepper Place will reopen walk-around farmers market; here are the new guidelines," 29 June 2020 Firefighters will monitor areas around the state this weekend as hot temperatures, dry conditions and gusty winds increase the risk for fires. Helena Wegner, The Arizona Republic, "Bighorn Fire burns 95,000 acres, evacuations remain in effect," 27 June 2020 Anyone potentially involved should closely monitor themselves for COVID-19 symptoms. James Weber, The Enquirer, "Practices canceled at Anderson High School until June 30 after positive COVID-19 test," 27 June 2020 Patrons who visited Cruisin' Chubbys Gentlemen's Club between June 10 and June 14 may have been exposed to the virus and should monitor themselves for symptoms, the Juneau's health department said in an advisory. Matt Piper, Milwaukee Journal Sentinel, "19 Wisconsin counties had 'high' coronavirus activity last week, according to new health department ratings," 23 June 2020 Oregon Public Broadcasting reports the Key to Oregon study, a project by Oregon Health & Sciences University and the Oregon Health Authority, aims to survey 100,000 Oregonians and monitor them for COVID-19. USA TODAY, "Airport number war, Navajo lockdowns, petition rules: News from around our 50 states," 18 June 2020 Columbus Public Health is telling people who attended George Floyd protests in the capital city during the early part of this week to monitor themselves for COVID-19 symptoms, Hancock reports. cleveland, "Ohio zoos, movie theaters, other attractions can reopen next week: Capitol Letter," 5 June 2020

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.

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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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Statistics for monitor

Last Updated

3 Jul 2020

Cite this Entry

“Monitor.” Dictionary, Merriam-Webster, Accessed 10 Jul. 2020.

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More Definitions for monitor


How to pronounce monitor (audio)

English Language Learners Definition of monitor

 (Entry 1 of 2)

: a device that shows information or images on a screen
: a device that is used to listen to sounds being made in another room
: a device that shows and records information about a condition or function of the body



English Language Learners Definition of monitor (Entry 2 of 2)

: to watch, observe, listen to, or check (something) for a special purpose over a period of time


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
monitored; monitoring\ ˈmän-​ət-​ə-​riŋ, ˈmän-​ə-​triŋ How to pronounce monitoring (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

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