Definition of "red" []

• The hue of the long-wave end of the visible spectrum, evoked in the human observer by radiant energy with wavelengths of approximately 630 to 750 nanometers; any of a group of colors that may vary in lightness and saturation and whose hue resembles that of blood; one of the additive or light primaries; one of the psychological primary hues. (noun)
• A pigment or dye having a red hue. (noun)
• Something that has a red hue. (noun)
• A Communist. (noun)
• A revolutionary activist. (noun)

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.

• "Heck even Twitter offered the #red hashtag which would turn your tweet red if you used it."
• "Orange (red + yellow) is opposite purple (blue +red), color wheel wise, but your point is taken."
• "There is no property of being red or hard although the disjuncts of the meaningful predicate ˜red or hard™ do"