What does monitor mean?
A monitor is most commonly an electronic screen that displays information from a computer or similar device. It can also refer to a person who supervises others, or to an instrument that displays or records measurements such as blood pressure. In verb form, to monitor means to observe or check something systematically over time, usually in order to detect changes, assess progress, or identify problems. The word often carries a practical or supervisory connotation: monitoring a system, a patient's condition, or a person's performance suggests attention to details and continued observation. Although technology has made the screen sense especially familiar, the older meaning of an overseer or watcher remains common in education, healthcare, business, and government. Monitor is also a standard shortened name for monitor lizards, large predatory lizards found across Africa, Asia, and Australia.
A screen or device that displays information, records measurements, or shows the status of a system; also, a person who observes or supervises an activity.
"A wall-mounted monitor shows the arrival time of each train."
When referring to a person, monitor is often used in formal contexts such as schools, workplaces, healthcare, and regulated industries.
To watch, check, or keep track of something over time, especially in order to detect changes or problems.
"The app monitors the battery level and temperature of the device."
This verb commonly occurs with processes, systems, symptoms, progress, performance, and activity.
Use "monitors" for multiple display screens, measuring devices, or people who perform a monitoring role.
"Security monitors helped the operators identify the source of the disturbance."
The word monitor entered English meaning “one who warns or oversees”; its familiar sense as a screen is a much later technological development.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does monitor come from?
The English word derives from the Latin noun monitor, meaning “one who warns, advises, or oversees,” which was formed from monēre, “to warn or admonish.” It entered English during the late 16th century for a person who supervised others or gave warnings. The later senses referring to display devices developed from the idea of something that receives, presents, or keeps track of information.
Related word forms
How monitor is actually used
In its noun senses, monitor commonly refers to a display screen or an overseeing person. As a verb, it usually implies regular observation rather than a single glance. The shortened form "monitor" for "monitor lizard" is especially common in British and South Asian English.