phototube[fōt′ō to̵̅o̅b′, -tyo̵̅o̅b′]
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio.
a vacuum tube designed to convert light energy into electrical energy by means of a photoemissive cathode
Origin: photo(electric) plush tube
Used by arrangement with John Wiley & Sons, Inc.
The American Heritage® Dictionary of the English Language, 4th edition Copyright © 2010 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
An electron tube with a photosensitive cathode.