colour tone
(US color tone)
noun
1A shade of a colour, especially one having a particular quality of brightness, deepness, or hue, or producing a particular effect within a picture or other image; (as a mass noun) the distinctive qualities or visual effect of a shade of colour.
2 Psychology the purity or intensity of a perceived colour ( rare ).
Origin
Mid 19th century; earliest use found in Elizabeth Sheppard (1830–1862), novelist.