primary colour

noun

1. Also calledadditive primary any of three spectral colours (usually red, green, and blue) that can be mixed to match any other colour, including white light but excluding black
2. Also calledsubtractive primary any one of the spectral colours cyan, magenta, or yellow that can be subtracted from white light to match any other colour. An equal mixture of the three produces a black pigment
3. Also calledpsychological primary any one of the colours red, yellow, green, or blue. All other colours look like a mixture of two or more of these colours and they play a unique role in the processing of colour by the visual system

Example Sentences

He was a primary colours politician — waspish, pugnacious, unrelenting, engaging — and at once complicated and undoubtedly controversial, in his politics and his personal conduct.

From BBC

But an hour and a bit of prime-time live television doesn’t offer much scope for that: it is a time for primary colours and punchy arguments.

From BBC

In various scientific phenomena -- such as primary colours or spatial dimensions -- three options are also enough to characterise different states.

From Science Daily

Prince switched up his look in 1991, combining intricate laces and primary colour with his notorious 'typhoon' hairdo.

From BBC

And this being Boris Johnson, we have a row in capital letters and primary colours.

From BBC