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 and Etymology of raster
borrowed from German Raster, originally, “screen used for printing halftones,” borrowed from Latin *rāster (presumed singular of rāstrī), rāstrum “hoe with two to six tines,” from rādere “to scrape, scratch, pare away, shave” + -trum, suffix of instruments (going back to Indo-European *-tro-) — more at rase
First Known Use: 1934
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