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 The teen pleaded guilty to an August vehicle theft and was on home detention with an ankle monitor awaiting sentencing when he was arrested again the day before his sentencing hearing., "13-year-old gets 7-year juvenile prison sentence for vehicle thefts in Champaign-Urbana," 20 Nov. 2020 During a routine check-in with federal immigration officials, Vanegas was given an ankle monitor and told to come back in a few months with her passport and a one-way ticket to her native Colombia. Monsy Alvarado, USA TODAY, "Her daughter is sick. She's caring for her grandchild. Now this New Jersey woman faces deportation, too.," 16 Nov. 2020 He was required to wear an electronic ankle monitor and follow certain conditions, including being prohibited from possessing any firearms and drinking alcohol. Tom Steele, Dallas News, "Family of slain woman relieved that accused killer, released on bond, is back behind bars," 30 Oct. 2020 His attorneys argued that he could safely be released on an ankle monitor to care for his elderly father, with whom Perilloux now lives. John Simerman,, "Jeff Perilloux, disgraced judge, jailed pending sentencing for fondling his daughters' friends," 15 Oct. 2020 Siahaan, an undocumented Indonesian immigrant who has lived in the United States for three decades, had been detained by U.S. Immigration and Customs Enforcement in February and released on an ankle monitor while legal appeals were pending. Washington Post, "ICE arrested an undocumented immigrant on church grounds. They lied to coax him out, family and attorney say.," 17 Sep. 2020 Defense attorney Eric Schwartzreich requested a low bond amount and quick fitting for a GPS ankle monitor so Squillace could be released from jail as soon as possible for health reasons. Wayne K. Roustan,, "Teenager charged 9 months after deadly 91 mph collision," 25 Aug. 2020 Yosuda is a popular bike brand among Shopping readers, and this model helps track your calories burned, speed, distance and time spent working out since it is displayed on the LCD monitor. Nicole Saunders, NBC News, "14 best affordable indoor spin bikes to up your home workout in 2020," 29 Oct. 2020 Peloton's stationary bikes cost almost $2,000 and users sign up for a $39-per-month subscription plan to view live classes on the bike's monitor. Dalvin Brown, USA TODAY, "Peloton recalls pedals on 27,000 stationary bikes due to leg injuries," 16 Oct. 2020 Recent Examples on the Web: Verb Governments must develop comprehensive conservation strategies and invest in technologies and practices to verify and monitor them. Eric Roston,, "A New UN Push Aims to Feed the World’s Rabid Hunger for Carbon Credits," 19 Nov. 2020 But asking students to install software to monitor them during a test raises a host of fairness issues, experts say. Avi Asher-schapiro, The Christian Science Monitor, "Online exams raise concerns of racial bias in facial recognition," 17 Nov. 2020 Gerszewski said the conditions were: no practice for the rest of the week, each swimmer had to travel to the meet separately and prior to the meet the swimmers and their families had to quarantine and monitor themselves for COVID-19 symptoms. Mark Stewart, Milwaukee Journal Sentinel, "After COVID-19 sacked Franklin football, the school's swimmers were thankful for the chance to compete at state," 16 Nov. 2020 As civil unrest erupted this year, powerful technologies were marshaled to monitor it and tamp it down. Darryn King, The Atlantic, "How Cyberpunk Predicted 2020," 14 Nov. 2020 The agency wanted to be able to monitor outcomes and track adverse events, according to the EUA. Washington Post, "White House sidestepped FDA to distribute hydroxychloroquine to pharmacies, documents show. Trump touted the pills to treat covid-19.," 31 Oct. 2020 Campbell also said in the email that the district will continue to track, monitor and study countywide and local ZIP code information from the Cuyahoga County Board of Health to help inform its decision. Ed Wittenberg, cleveland, "Orange Schools aim for return to in-person learning Nov. 2, if Cuyahoga County stays ‘red’," 25 Oct. 2020 Paul Petit, the public health director for Genesee and Orleans County, has encouraged wedding goers to monitor themselves for symptoms of the novel virus through this weekend. Madeline Farber, Fox News, "Wedding guests warned of coronavirus exposure following New York event: officials," 28 Oct. 2020 Anyone who took that route on that day is encouraged to monitor themselves for symptoms, TARC officials said. Ayana Archie, The Courier-Journal, "TARC bus driver tests positive for coronavirus. Were you on Route 25?," 23 Oct. 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

24 Nov 2020

Cite this Entry

“Monitor.” Dictionary, Merriam-Webster, Accessed 4 Dec. 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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