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, ˌmɒnɪˈtɔːrɪəl /

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

It was "something we are just going to have to potentially live with and monitor carefully," he added.

From BBC ● Jul. 28, 2026

Beta cells in the pancreas monitor blood sugar levels.

From Science Daily ● Jul. 28, 2026

Investors will closely monitor the BOJ’s two-day meeting starting Thursday, where the central bank is widely expected to leave rates unchanged.

From The Wall Street Journal ● Jul. 27, 2026

For some, though, this only strengthened their resolve to monitor agents to make sure they didn’t kill others.

From Slate ● Jul. 27, 2026

There was also a video monitor where you could watch and listen to what was going on in the dining room.

From "The Smartest Kid in the Universe" by Chris Grabenstein

The civil war has seeded instability across Myanmar, creating fertile ground for organised crime groups running transnational scam operations to set up shop in fortified compounds, according to monitors.

From Barron's ● Jul. 28, 2026

The inquiry had previously heard "grave concerns" expressed about the widespread use of Oxevision technology, which monitors patients in their rooms using infrared sensors and cameras.

From BBC ● Jul. 24, 2026

So we stock up on air purifiers, now an $18 billion industry, along with indoor air quality monitors and subscription air filter services.

From Salon ● Jul. 19, 2026

Then, he turned back to his two monitors, and kept prompting.

From The Wall Street Journal ● Jul. 19, 2026

Glancing up, I saw frozen images on all three monitors showing the same Butterfly in various degrees of capture.

From "Glitch" by Laura Martin

During the cruise, the magnetometer has continuously monitored the magnetic field carried by the solar wind.

From Science Daily ● Jul. 28, 2026

A Bay Area resident stuck on a cruise ship with a deadly hantavirus outbreak has returned to Santa Clara County and is being monitored by health officials.

From Los Angeles Times ● Jul. 28, 2026

People with an increased risk of type 2 diabetes participated in a two-year lifestyle program and were then monitored for approximately nine years.

From Science Daily ● Jul. 28, 2026

As a result, his minutes were carefully monitored throughout the tournament, with the forward starting only three of England's eight matches.

From BBC ● Jul. 19, 2026

Davy baked and left cookies on my bed, and she always monitored my health and mothered me with homemade soup when I was sick.

From "Hole in My Life" by Jack Gantos

"That's what attachment is about. It's a monitoring system for safety."

From BBC ● Jul. 28, 2026

It also has applications in biomedical science, agriculture, environmental monitoring, and astrophysics.

From Science Daily ● Jul. 28, 2026

Much of the overtime money the department spent went instead toward preparing for unrest, monitoring protests and vigils, guarding hotels housing federal agents, and managing the public response to federal violence.

From Slate ● Jul. 27, 2026

Most investors expect the Fed to hold rates steady at 3.50-3.75 percent for the fifth straight meeting, according to CME's FedWatch monitoring tool.

From Barron's ● Jul. 26, 2026

“We’re monitoring the situation in New Orleans closely,” Evergreen says again.

From "The Manifestor Prophecy" by Angie Thomas

Related Words

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