About

A subtractive combination of colors, as in mixing of pigments, inks or dyes for painting or printing.

Subtraction comes from the fact that when the light is reflected on the surface, it's filtered.

Subtractive primaries color are also known as Minus color

On a color wheel, they are located a 120 degree of each other.

Minus Color Wheel

For any colorspace, the plus color (ie additive color) are the opposites (complementray color) of the minus color

This mixing are valid for all subtractive colorspaces (even if the most known is CYMK): <MATH> \begin{array}{rrrl} & & blue & + & red & = & purple \\ & & blue & + & yellow & = & green \\ & & red & + & yellow & = & orange \\ \end{array} </MATH>

Colorspace

CMYK

Printers and others who use modern subtractive color methods and terminology use mostly as subtractive primaries color:

This is known as the Cyan Magenta Yellow Black Colorspace

Note that as:

Minus Color Vs Plus Color

RYB

In a RYB colorspace, the subtractive primaries color are:

Ryb 1)