CMYKColor

CMYKColor[c,m,y,k] represents a color in the CMYK color space with cyan, magenta, yellow and black components.

CMYKColor[c,m,y,k,a] specifies opacity a. 

CMYKColor["string"] returns a color from an HTML color name etc.

CMYKColor[color] returns the CMYK representation of color.

Please visit the official Wolfram Language Reference for more details and examples on core symbols.