Monitor > define

noun

• Someone who supervises (an examination.
  • synonyms: proctor
• Someone who gives a warning so that a mistake can be avoided.
  • synonyms: admonisher, reminder
• An ironclad vessel built by Federal forces to do battle with the Merrimac.
• Display produced by a device that takes signals and displays them on a television screen or a computer monitor.
  • synonyms: monitoring device
• Electronic equipment that is used to check the quality or content of electronic transmissions.
• A piece of electronic equipment that keeps track of the operation of a system continuously and warns of trouble.
• Any of various large tropical carnivorous lizards of Africa and Asia and Australia; fabled to warn of crocodiles.
  • synonyms: monitor lizard, varan

verb

• Keep tabs on; keep an eye on; keep under surveillance.
  • usage: "we are monitoring the air quality"; "the police monitor the suspect's moves"
  • synonyms: supervise
• Check, track, or observe by means of a receiver. .

• (n.) An ironclad war vessel, very low in the water, and having one or more heavily-armored revolving turrets, carrying heavy guns.
• (n.) One who admonishes; one who warns of faults, informs of duty or gives advice and instruction by way of reproof or caution.
• (n.) Hence, specifically, a pupil selected to look to the school in the absence of the instructor, to notice the absence or faults of the scholars or to instruct a division or class.
• (n.) Any large Old World lizard of the genus Varanus; especially, the Egyptian species (V. Niloticus), which is useful because it devours the eggs and young of the crocodile. It is sometimes five or six feet long.
• (n.) A tool holder, as for a lathe, shaped like a low turret, and capable of being revolved on a vertical pivot so as to bring successively the several tools in holds into proper position for cutting.
• (n.) A monitor nozzle.

Generally, is to keep tabs on; keep an eye on; or, keep under surveillance. In business, it is a person or firm appointed to review and report on, without controlling or approving, the day-to-day transactions of a business. Particulars of the engagement are usually set out in an exchange of letters, an agreement or court order.