Full Idea
Colour charge is 'three-dimensional'. As well as the charge having a positive or negative sign, it can also have a direction, and for convenience these three different directions (pointing like a weather vane) are labelled 'red', 'green' and 'blue'.
Gist of Idea
Colour charge is positive or negative, and also has red, green or blue direction
Source
Gavin Hesketh (The Particle Zoo [2016], 04)
Book Reference
Hesketh,Gavin: 'The Particle Zoo' [Quercus 2016], p.81
Related Idea
Idea 21197 Standard Model forces are one- two- and three-dimensional [Hesketh]