1mon·i·tor 
/ˈmɑ:nətɚ/ noun
plural mon·i·tors /ˈmɑ:nətɚ/ noun [count] 1 : a device that is used for showing, watching, or listening to something: such as a : a device that shows information or images on a screen
▪ a computer monitor ▪ a television monitor ▪ They watched the press conference on a video monitor in a back room. — see pictures at camera, computer
b : a device that is used to listen to sounds being made in another room
▪ We put a baby monitor in the nursery.
c : a device that shows and records information about a condition or function of the body
▪ a heart monitor 2 : a student who helps the teacher at a school
▪ (US) He was chosen to be a hall monitor. [=a student who watches the hallways for bad behavior] 3 : a person who has the job of checking or watching some activity or behavior
▪ U.N. weapons monitors and inspectors
▪ a computer monitor ▪ a television monitor ▪ They watched the press conference on a video monitor in a back room. — see pictures at camera, computer
b : a device that is used to listen to sounds being made in another room
▪ We put a baby monitor in the nursery.
c : a device that shows and records information about a condition or function of the body
▪ a heart monitor
▪ (US) He was chosen to be a hall monitor. [=a student who watches the hallways for bad behavior]
▪ U.N. weapons monitors and inspectors
