a vacuum tube in which a stream of electrons is electromagnetically focused on a fluorescent screen, producing lighted dots: such tubes are used as oscilloscopes and picture tubes: abbrev. CRT
See cathode-ray tube in American Heritage Dictionary 4
(kăthˈōd-rāˌ)
noun Abbr. CRT
A vacuum tube in which a hot cathode emits electrons that are accelerated as a beam through a relatively high voltage anode, further focused or deflected electrostatically or electromagnetically, and allowed to fall on a phosphorescent screen.