Main Entry: ras·ter

Pronunciation: \ˈras-tər\

Function: noun

Etymology: German, from Latin raster, rastrum rake, from radere to scrape

Date: 1934

: a scan pattern (as of the electron beam in a cathode-ray tube) in which an area is scanned from side to side in lines from top to bottom; also : a pattern of closely spaced rows of dots that form an image (as on the cathode-ray tube of a television or computer display)