A non-spectral colour is a colour that is not present in the visible spectrum and cannot be produced by a single wavelength or narrow band of wavelengths of light.
- While spectral colours are evoked by a single wavelength of light in the visible spectrum, non-spectral colours are produced by a combination of spectral colours from different parts of the spectrum.
- Colours evoked by a single wavelength of light are often described as being produced by monochromatic light.
- Magenta, pink, cyan and brown are examples of non-spectral colours produced by combining different wavelengths of light:
- Blue and red = magenta
- Red and purple = pink
- Blue and green = cyan
- Red, yellow and blue = brown