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definitions

bitmap

or bit map

[bit-map]
noun
  1. a piece of text, a drawing, etc., represented, as on a computer display, by the activation of certain dots in a rectangular matrix of dots.
Related formsbit·mapped, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for bitmap

bitmap

noun computing
  1. a picture created on a visual display unit where each pixel corresponds to one or more bits in memory, the number of bits per pixel determining the number of available colours
verb -maps, -mapping or -mapped
  1. (tr) to create a bitmap of
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for bitmap
n.

1973, in computer jargon, from bit (n.2) + map. Literally, a map of bits.

Online Etymology Dictionary, © 2010 Douglas Harper
bitmap in Science

bitmap

[bĭt′măp′]
Computer Science
  1. A set of bits that represents a graphic image. Each bit or group of bits corresponds to a pixel in the image. Optical scanners and fax machines convert text or pictures into bitmaps.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.