monitor

1 of 2

noun

mon·​i·​tor ˈmä-nə-tər How to pronounce monitor (audio)
1
a
: 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
2
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
monitorial adjective
monitorship noun

monitor

2 of 2

verb

monitored; monitoring ˈmä-nə-t(ə-)riŋ How to pronounce monitor (audio)

transitive verb

: to watch, keep track of, or check usually for a special purpose
Nurses monitored the patient's heart rate.

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.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Noun
Many of these juveniles are relegated to home detention and are required to wear a GPS ankle monitor. Reader Commentary, Baltimore Sun, 11 July 2025 According to Card Ladder, an online card sales monitor, these two sales are around seven times higher than the previous most expensive Alcaraz card. Larry Holder, New York Times, 11 July 2025
Verb
Residents and travelers are urged to monitor official updates from the NPS for instructions and park reopening information. Hollie Silverman, MSNBC Newsweek, 12 July 2025 Image courtesy of the researchers View gallery - 4 images Researchers from the California Institute of Technology (Caltech) have developed a wireless smart capsule packed with sensors and other tiny electronics to monitor the workings of your gastrointestinal (GI) tract. Abhimanyu Ghoshal, New Atlas, 12 July 2025 See All Example Sentences for monitor

Word History

Etymology

Noun and Verb

Latin, one that warns, overseer, from monēre to warn — more at mind

First Known Use

Noun

1530, in the meaning defined at sense 1a

Verb

1924, in the meaning defined above

Time Traveler
The first known use of monitor was in 1530

Browse Nearby Words

Cite this Entry

“Monitor.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/monitor. Accessed 15 Jul. 2025.

Kids Definition

monitor

1 of 2 noun
mon·​i·​tor ˈmän-ət-ər How to pronounce monitor (audio)
1
a
: a student appointed to assist a teacher
b
: a person that warns or instructs
c
: one that monitors or is used in monitoring
especially : a video screen used for display (as of television pictures or computer information)
2
3
a
: a heavily armored warship having low sides and revolving guns that was used against shipping in harbors and in river patrol
b
: a gunboat used to bombard coastal areas and riverbanks

monitor

2 of 2 verb
monitored; monitoring ˈmän-ət-ə-riŋ How to pronounce monitor (audio)
ˈmän-ə-triŋ
: to watch, observe, or check for a special purpose
monitor a broadcast for sound quality

Medical Definition

monitor

1 of 2 noun
mon·​i·​tor ˈmän-ət-ər How to pronounce monitor (audio)
: one that monitors
especially : a device for observing or measuring a biologically important condition or function
a heart monitor

monitor

2 of 2 transitive verb
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

More from Merriam-Webster on monitor

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