Magenta is the second of the three primary colors in CMYKWhat is CMYK? Cyan, Magenta, Yellow, and Black (or Key) are the four colors of ink used in four-colo... More. M stands for Magenta. The color can be described as pink. CMYK is a subtractiveCMYK (cyan, magenta, yellow, black ) is a subtractive color model. The colors of ink added together ... More model.