monitor

American  

[mon-i-ter] / ˈmɒn ɪ tər /

noun

• monitors
  plural

1. (especially formerly) a student appointed to assist in the conduct of a class or school, as to help take attendance or keep order.

2. a person appointed to supervise students, applicants, etc., taking an examination, chiefly to prevent cheating; proctor.

3. a person who admonishes, especially with reference to conduct.

4. something that serves to remind or give warning.

5. a device or arrangement for observing, detecting, or recording the operation of a machine or system, especially an automatic control system.

6. an instrument for detecting dangerous gases, radiation, etc.

7. Radio and Television.

   1. a receiving apparatus used in a control room, especially to provide a steady check of the quality of an audio or video transmission.

   2. a similar apparatus placed in various parts of a studio so that an audience can watch a recorded portion of a show, the performer can see the various segments of a program, etc.

   3. any such receiving apparatus used in a closed-circuit system, as in an operating room.

8. Computers.

   1. the screen component of a computer, especially a free-standing screen.

   2. a control program.

   3. a group of systems used to measure the performance of a computer system.

9. Nautical.

   1. a former U.S. steam-propelled, armored warship of very low freeboard, having one or more turrets and used for coastal defense.

   2. (initial capital letter, italics) the first of such warships, used against the Confederate ironclad warship Merrimac at Hampton Roads, Va., in 1862.

10. a raised construction straddling the ridge of a roof and having windows or louvers for lighting or ventilating a building, as a factory or warehouse.

11. an articulated mounting for a nozzle, usually mechanically operated, which permits a stream of water to be played in any desired direction, as in firefighting or hydraulic mining.

12. Also called giant.  (in hydraulic mining) a nozzle for dislodging and breaking up placer deposits with a jet of water.

13. any of various large lizards of the family Varanidae, of Africa, southern Asia, the East Indies, and Australia, fabled to give warning of the presence of crocodiles: several species are endangered.

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verb (used with object)

• monitors,
  present (3rd person singular)
• monitored,
  past participle,  past
• monitoring
  present participle

1. Radio and Television.

   1. to listen to (transmitted signals) on a receiving set in order to check the quality of the transmission.

   2. to view or listen to (television or radio transmissions) in order to check the quality of the video or audio.

   3. to listen to (a radio conversation or channel); keep tuned to.

2. to observe, record, or detect (an operation or condition) with instruments that have no effect upon the operation or condition.

3. to oversee, supervise, or regulate.

   to monitor the administering of a test.

4. to watch closely for purposes of control, surveillance, etc.; keep track of; check continually.

   to monitor one's eating habits.

verb (used without object)

• monitors,
  present (3rd person singular)
• monitored,
  past participle,  past
• monitoring
  present participle

1. to serve as a monitor, detector, supervisor, etc.

monitor British  

/ ˈmɒnɪtə /

noun

1. a person or piece of equipment that warns, checks, controls, or keeps a continuous record of something

2. education

   1. a senior pupil with various supervisory duties

   2. a pupil assisting a teacher in classroom organization, etc

3. a television screen used to display certain kinds of information in a television studio, airport, etc

4. the unit in a desk computer that contains the screen

5. 1. a loudspeaker used in a recording studio control room to determine quality or balance

   2. a loudspeaker used on stage to enable musicians to hear themselves

6. a device for controlling the direction of a water jet in fire fighting

7. any large predatory lizard of the genus Varanus and family Varanidae, inhabiting warm regions of Africa, Asia, and Australia See also Komodo dragon

8. Also called: giant.  mining a nozzle for directing a high-pressure jet of water at the material to be excavated

9. (formerly) a small heavily armoured shallow-draught warship used for coastal assault

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verb

1. to act as a monitor of

2. to observe or record (the activity or performance) of (an engine or other device)

3. to check (the technical quality of) (a radio or television broadcast)

monitor Scientific  

/ mŏn′ĭ-tər /

1. A device that accepts video signals from a computer and displays information on a screen. Monitors generally employ cathode-ray tubes or flat-panel displays to project the image.

2. See Note at pixel

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Other Word Forms

Derived Forms

• monitorship
  noun
• monitress
  noun
• monitorial
  adjective
• self-monitoring
  adjective
• unmonitored
  adjective
• monitorially
  adverb

Inflected Forms

Nouns

• monitors
  plural

Participles

• monitoring
  present
• monitored
  past

Conjugated Forms

Present

• monitor
  simple
• monitors
  simple
• have monitored
  perfect
• has monitored
  perfect
• am monitoring
  progressive
• are monitoring
  progressive
• is monitoring
  progressive
• have been monitoring
  perfect progressive
• has been monitoring
  perfect progressive

Past

• monitored
  simple
• had monitored
  perfect
• was monitoring
  progressive
• were monitoring
  progressive
• had been monitoring
  perfect progressive

Future

• will monitor
  simple
• will have monitored
  perfect
• will be monitoring
  progressive
• will have been monitoring
  perfect progressive

Etymology

Origin of monitor

First recorded in 1540–50; from Latin: “prompter, adviser,” equivalent to monit(us) “reminded” (past participle of monēre) + -or -or

Explanation

A monitor is a device or a person who watches or checks to see that all is going well. If you're babysitting, you might use a baby monitor so you can hear if the baby cries in its sleep. Monitor can be used as a noun or a verb, both of which are concerned with watching over someone or something. A heart monitor displays the rhythm of your heart. A hall monitor is a person who checks to see that students aren't wandering the halls. If you are monitoring your grades, you are keeping track of them to see if they go up or down. And some parents buy a program that will monitor your Internet use, though you might think that this is an invasion of privacy.

Example Sentences

See Examples For:

monitor monitors monitored monitoring

Given how precarious the slope was, the group decided Mingma G would hang back and monitor by drone, instructing the three climbers.

From BBC ● Sep. 11, 2026

Anthony Allman, executive director of Vets Advocacy, a nonprofit created to monitor the settlement of the earlier lawsuit, said a neutral process is needed to find out what veterans want.

From Los Angeles Times ● Sep. 11, 2026

But it’s something to monitor, he noted, given Thursday’s violent moves in shorter-dated Treasury yields, fueled by the rising odds of a Fed rate hike and jolt higher in oil prices.

From MarketWatch ● Sep. 10, 2026

The women monitor a smartphone app to track alerts for Russian airstrikes.

From The Wall Street Journal ● Sep. 6, 2026

Since 1980, an important tool has become the ability to remotely monitor volcanoes from space using satellites.

From "Mountain of Fire" by Rebecca E. F. Barone

Working within the international system coordinated by UNESCO, it monitors earthquakes that could generate tsunamis and sends initial messages to French emergency authorities and other warning centers.

From Science Daily ● Sep. 10, 2026

The agency also monitors cases of diarrhoea brought on by reduced access to clean water due to the drought, with 225 cases so far this month.

From Barron's ● Sep. 8, 2026

Black Point Beach Association has a handyman to maintain signs and locks; a warden monitors the beach to enforce its rules.

From The Wall Street Journal ● Sep. 3, 2026

The FSB which Bailey leads is a global watchdog which monitors finance ministry officials, banks and securities regulators.

From BBC ● Aug. 31, 2026

He pressed a button on a clicker, and half a dozen pictures filled the wall monitors.

From "City Spies" by James Ponti

The table below lists stocks of companies based outside the U.S. that currently are recommended by any of the investment newsletters monitored by my performance auditing firm.

From MarketWatch ● Sep. 11, 2026

AI optimists are confident the technology is just being tested and monitored enough that humans can prevent it from consistently causing catastrophes.

From Los Angeles Times ● Sep. 11, 2026

They were given first aid before being taken to Nandankanan Zoological Park in the state capital, Bhubaneswar, where they are in quarantine and being monitored.

From BBC ● Sep. 9, 2026

Fusion systems require multiple models because different parts of the machine and plasma must be monitored and controlled at the same time.

From Science Daily ● Sep. 6, 2026

An electronic bracelet on their ankle monitored their moves.

From "Red Kayak" by Priscilla Cummings

“But it should be slower than it otherwise could be; interventions like safety cases and monitoring have significant costs.”

From The Wall Street Journal ● Sep. 14, 2026

On Saturday, the head of the US AI company Anthropic, Dario Amodei, proposed a plan that includes global regulation, industry-wide regulation and independent monitoring of AI models as they are developed.

From BBC ● Sep. 14, 2026

The European Commission said national data protection authorities were "responsible for monitoring and enforcing" privacy rules.

From Barron's ● Sep. 12, 2026

Admittedly, these are anecdotes not data: the Big Wasp Survey – the only national wasp monitoring survey – is yet to start sampling this summer.

From Science Daily ● Sep. 11, 2026

The monitoring ABI agents were left with nothing to suggest any relationship between Myers and McMillian and plenty of evidence indicating that the two men had never met.

From "Just Mercy" by Bryan Stevenson

Related Words

• audit
• check
• control
• follow
• keep an eye on
• observe
• oversee
• scan
• supervise
• survey
• track