Abbreviation for red, green, blue, the additive color primaries.<br><br>Red green blue. An additive system for representing the color spectrum using combinations of red, green and blue. Used in theatrical lighting and in video display devices. Blue + Green = Cyan Red + Blue = Magenta Green + Red = Yellow Blue + Green + Red = WhiteAlso see CMYK, colorblind, color wheel, primary colors, and secondary colors.