Translation of "monitor x-y" into English

A CRT (cathode-ray tube), commonly used in oscilloscopes and DVST (direct view storage tube) displays, that allows the electron beam to be arbitrarily deflected, based on x-y-coordinate signals. For example, to draw a line on a vector display, the video adapter sends signals to the X and Y yokes to move the electron beam over the path of the line; there is no background composed of scan lines, so the line drawn on the screen is not constructed of pixels.