Accent
An accent is a typically bright color that contrasts with the more utilitarian background and foreground colors within a color scheme. These are present in the visual style of many platforms (though not all).
On the web, an accent is sometimes used in <input> elements for the active portion of the control, for instance, the background of a checked checkbox.
See also
CSS related to the accent
You can set the color of the accent for a given element by setting the element's CSS accent-color property to the appropriate <color> value.