cathode-ray tube

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A vacuum tube, used in monitors and televisions, 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.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun a vacuum tube in which electrons from a heated cathode are focused and deflected onto a phosphorescent screen; used in television sets etc

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a vacuum tube in which a hot cathode emits a beam of electrons that pass through a high voltage anode and are focused or deflected before hitting a phosphorescent screen