Tint

Tint, shade and tone are the three ways a pigment gets modified: white makes a tint, black makes a shade, and grey makes a tone. The words come from paint and they survive in interfaces because the operations still describe what a palette generator is doing. A ten step blue ramp is, roughly, a stack of tints above the base and a stack of shades below it.

In products, tints do the quiet work. The pale fill behind a selected row, the background of an informational banner, the wash a menu item takes on hover, the badge that has to be legible with dark text on it: all of these want a colour that is unmistakably the accent hue but far too light to compete with the accent itself. Getting them from the same base as the accent is what keeps a screen looking like one product rather than a collection of light blues.

How the mixing is done matters more than it sounds. Blending toward white in sRGB is not perceptually even, so equal numeric steps produce a ramp that crowds at one end; mixing in a perceptual space such as oklab spaces them the way the eye reads them. A tint is also not the same thing as lowering opacity. An opaque tint is a known colour; a translucent one is whatever it happens to be sitting on, which is how the same badge ends up passing contrast on a card and failing it on a striped table.

Dark themes are where the word gets slippery. A tint that reads as subtle against white glares against a dark surface, so the equivalent role in a dark theme is usually filled by a shade of the same hue, or by the accent at very low chroma. Apple’s use of “tint colour” is a separate sense again: there it means the accent colour itself, not a lightened version of anything.