From Longman Dictionary of Contemporary Englishscreen saverˈscreen ˌsaver noun [countable] a computer program that makes a moving image appear on the screen when the image on it has not changed for a period of time, especially so that the screen does not become damaged
Examples from the Corpus
screen saver• One path to self-indulgence lies in having just the right level of tastelessness for a screen saver on your computer.• It's a screen saver, yes, but that's only where it starts.• In addition to ads, the screen saver features the information crawl at the bottom of the screen.• Facilities like the screen saver that's built in are redundant with Windows 3.1, but with version 3.0, are useful. 