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 Last month, still attached to hospital monitors, 50-year-old Christopher Grant told CNN’s Chris Cuomo how he was shot on Aug. 3 inside of a Walmart in El Paso, Texas. Jasmine Aguilera, Time, "He Was Wounded in the El Paso Shooting and Lauded for His Bravery. Now Police Say His Heroic Story Isn't True," 11 Sep. 2019 And a recent report by an independent monitor overseeing claims of government noncompliance with Flores rules detailed the extreme overcrowding and poor conditions that immigrant youths faced in detention. Anchorage Daily News, "Trump administration moves to end limits on detention of migrant children," 21 Aug. 2019 And a recent report by an independent monitor overseeing claims of government noncompliance with Flores rules detailed the extreme overcrowding and poor conditions that immigrant youths faced in detention. Fortune, "Trump Administration Moves to End Limits on Child Detention," 21 Aug. 2019 Last year, the state Department of Water Resources proposed requiring that all wells pumping more than 35 gallons a minute monitor and report their water use. Andrew Stern, NBC News, "Draining Arizona: Residents say corporate mega-farms are drying up their wells," 17 Sep. 2019 All industries that involve the production of consumer goods from raw materials use process technicians to control, monitor and troubleshoot those transformation processes. Cheryl P. Rose, Houston Chronicle, "Process technicians earn strong wages for serious responsibilities," 16 Sep. 2019 The repurposed room contains eight 3D printers, a laser cutter, a vinyl cutter, a computerized sewing and embroidery machine, computer monitors to program the equipment, tables to work and soft chairs to sit in to collaborate. Steve Sadin,, "Creativity catches on at Deerfield High School," 16 Sep. 2019 As part of the transition, the county also introduced an outside contract monitor that provides monthly reports on Wellpath's success. Alison Dirr, Milwaukee Journal Sentinel, "Report recommends against Milwaukee County moving inmate medical services in-house," 13 Sep. 2019 Less work stress and pain means higher productivity, and today many companies have internal experts who are trained in how to set up desks, chairs, keyboards and monitors to meet each person's needs. Sandee Lamotte, CNN, "Sit, stand, sit: The new science about how to best use your standing desk," 12 Sep. 2019 Recent Examples on the Web: Verb Four other waves to watch In addition to Humberto there are four other areas being monitored by the hurricane center for development. Leigh Morgan, al, "Tropical Storm Humberto 2019 tracks near storm-weary Bahamas but no U.S. threat," 14 Sep. 2019 The front doors to the hotel or motel rooms must be monitored by a security camera. Martin E. Comas,, "Casselberry, popular with mom-and-pop motels before I-4 and Disney, looks at regulations to attract new hotels," 12 Sep. 2019 While some injured student-athletes receive treatment in a sports clinic and are monitored by an athletic trainer, others receive little guidance on how to safely return to their normal activities. Susan Davies, The Conversation, "Concussions and children returning to school – what parents need to know," 12 Sep. 2019 Daytime flows from the dam will be reduced during the operation, which will be monitored by the U.S. Coast Guard. oregonlive, "Sunken tugboat to be removed from Columbia River near Bonneville Dam," 11 Sep. 2019 Conducted in partnership with the will detect noise levels monitored by the Wathc. Irina Ivanova, CBS News, "Annual Apple event promises new iPhone, watch models against a backdrop of slowing sales," 10 Sep. 2019 The fact that the Denver Sheriff Department conducted an internal investigation and found no wrongdoing on the part of the deputies or staff is a clear sign that the department needs to be monitored by an outside entity. Dp Opinion, The Denver Post, "Letters: Pregnant inmate deserved help; Voters will get final say; Seeing red at Colorado game (9/9/19)," 9 Sep. 2019 Report cards are monitored by volunteer teacher Storm McCullough and every Monday several academic scholar students from Boyd Anderson High School provide free tutoring. Emmett Hall,, "Lauderdale Lakes Vikings open season with optimism on and off the field," 5 Sep. 2019 The cameras not only record and store images for at least 45 days, they are continuously monitored by a security officer in a command center, said Kevin Simpson, the district’s director of security. Kimberly Fornek,, "Hinsdale District 86 security measures include nearly 300 surveillance cameras and armed security officers," 3 Sep. 2019

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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Statistics for monitor

Last Updated

3 Nov 2019

Time Traveler for monitor

The first known use of monitor was in 1530

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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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Comments on monitor

What made you want to look up monitor? Please tell us where you read or heard it (including the quote, if possible).


meddlesome, informal, or unofficial

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