Dictionary.com
Thesaurus.com
Synonyms

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.


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

    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

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

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

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

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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

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)

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
monitor Scientific  
/ mŏnĭ-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


Other Word Forms

Derived Forms

Inflected Forms

Nouns

Participles

Conjugated Forms

Present

Past

Future

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.

Keep Reading on Vocabulary.com

Vocabulary lists containing monitor

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

The allegations in these indictments apparently are that they went beyond exaggerating the threats and actually supported these organizations to make them bigger threats so they could then monitor them or do whatever they did.

From Slate Aug. 22, 2026

That’s according to Goldman Sachs’ hedge fund trend monitor that published Thursday and encompasses almost 1,000 funds with $5.4 trillion of gross equity positioning.

From MarketWatch Aug. 21, 2026

The next morning, the judge named attorney Andrea Sheridan Ordin as special master and Dr. Paul H. Wise as independent monitor to enforce the agreement, over the objections of federal officials.

From Los Angeles Times Aug. 19, 2026

Appliance maker SharkNinja is building a tool to allow its finance team to monitor profitability in real time, potentially shaving weeks off the cumbersome process of building a forecast.

From The Wall Street Journal Aug. 18, 2026

The monitor frowns and asks another monitor, “Where’d this come from?”

From "Isaiah Dunn Is My Hero" by Kelly J. Baptist

Even front-of-the-house sound engineer as well as our in-ear monitors, everybody is playing a part.

From Los Angeles Times Aug. 21, 2026

Beneath the market’s daily surface, algorithmic money is always in motion, sliding out of one corner and into another as the signals it monitors shift.

From The Wall Street Journal Aug. 11, 2026

An international team of atmospheric scientists and wildfire specialists monitors these unusual clouds.

From Science Daily Aug. 5, 2026

UN human rights monitors have voiced concern about rising numbers of civilian casualties, which have reached their highest level since Russia's invasion in February 2022.

From Barron's Aug. 5, 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

Still, Goldman executives prized Situational, they told clients, though the bank monitored the fund because its portfolio was so concentrated and levered, according to a person familiar with the matter.

From The Wall Street Journal Aug. 17, 2026

But as they monitored his response, it became clear he wasn’t going to be ready.

From Los Angeles Times Aug. 15, 2026

According to A/Prof Larcombe, increasing CO2 may need to be considered not only as an environmental concern, but also as a long-term public health factor that should be monitored.

From Science Daily Aug. 15, 2026

A wildfire started in the area on 15 July and the incident, which has burned through thousands of acres of woodland and moor, continues to be monitored for hotspots.

From BBC Aug. 14, 2026

Having bought tickets in hopes of seeing Lincoln and Grant, the theatergoers have monitored the state box, only to find it empty.

From "Lincoln's Last Days: The Shocking Assassination that Changed America Forever" by Bill O'Reilly

An Oldham Council spokesperson said: "As a result, the council's monitoring officer will write to the Secretary of State to formally advise of the situation."

From BBC Aug. 21, 2026

And, amid a cash crunch triggered by a federal investigation into insurance firms his companies control, potential bidders for the Dodgers are monitoring the situation closely.

From Los Angeles Times Aug. 21, 2026

Former employees say the two couples have spent the years since Megxit monitoring one another, always making sure to counter any positive media coverage by planting their own.

From The Wall Street Journal Aug. 20, 2026

The birds, in turn, are accustomed to floodlights for the "penguin parade" tourist attraction, as well as being periodically handled by veterinarian scientists for monitoring of their health.

From Barron's Aug. 20, 2026

“Commander Root, you are monitoring all channels I presume....”

From "Artemis Fowl" by Eoin Colfer

Vocabulary.com logo
by dictionary.com

Join 12,000,000 vocabulary learners

Start learning new words today on VocabTrainer.
You'll remember them forever.

Start training