Definition of: monitor

(mon′ə·tər) noun
1. One who advises or cautions.
2. A senior pupil placed in charge of a dormitory or class.
3. Something that warns or advises; a reminder.
4. Nav. An ironclad vessel having a low, flat deck and low freeboard, and fitted with a blister and with one or more turrets carrying heavy guns; specifically, the first vessel of the type, “The Monitor.” See MERRIMAC.
5. Zool. Any of several large carnivorous lizards (family Varanidae) of the Old World tropics; especially, the East Indian kabara-goya (Varanus salvator), which reaches a length of seven feet.
6. Mining A contrivance, consisting of nozzle and holder, whereby the direction of a stream can be readily changed.
7. Telecom. a A high-fidelity loudspeaker in the control-room of a radio studio, used to insure adequate sound transmission. b A receiver for listening to a station's broadcasts to check on quality and frequency of transmission, compliance with laws, material transmited, etc.
—v.t.
1. Telecom. To listen to (a station, broadcast, etc.) with or as with a monitor.
2. To have charge of (a person or group) as a monitor.
3. To keep watch over or check as a means of control: to monitor tax returns. [<L <monitus. See MONITION.]