Meaning of electron-ray tube

e•lec'tron-ray tube"

Pronunciation: (i-lek'tron-rā"), [key]
— Electronics. Electronics.
  1. a small cathode-ray tube having a fluorescent screen on which the pattern varies with the voltage applied to the grid: used chiefly in radio receivers to indicate accuracy of tuning. Also called
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.