Definition of raster
: 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)
Origin of raster
German, from Latin raster, rastrum rake, from radere to scrape
First Known Use: 1934
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