Definition of "decolorize" []

• To remove the color from. (verb-transitive)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Manganese dioxide is used to: manufacture ferroalloys; manufacture dry cell batteries (it's a depolarizer); to "decolorize" glass; to prepare some chemicals, like oxygen and chlorine; and to dry black paints."
• "April 29th, 2008 6: 11 pm ET yeah right CNN ... put HILLIARys sign in front and decolorize Obama's sign to look darker. i expected better from CNN ... sheesh!"
• "Import it into Photoshop, or similar, then decolorize it, turn up the contrast and lightness accordingly."