ra·dar 
/ˈreɪˌdɑɚ/ noun
plural ra·dars /ˈreɪˌdɑɚ/ noun : a device that sends out radio waves for finding out the position and speed of a moving object (such as an airplane) [count] ▪ a powerful radar [noncount] ▪ The approaching planes were detected by radar. — often used figuratively in informal U.S. English ▪ A career in politics wasn't even on my radar (screen) at that point. [=I wasn't thinking at all about a career in politics] ▪ an actor who has fallen off the radar [=who has stopped being noticed or talked about] ▪ He tried to stay under the radar [=unnoticed] as he went about his business.
