What term describes a color that has been grayed by its complement or gray addition?

The term that accurately describes a color that has been grayed by its complement or by the addition of gray is "tone." When you take a pure color and mix it with its complementary color or add gray, you create a tone of that color. This process changes the intensity or purity of the color, resulting in a more subdued and desaturated version, which is referred to as a tone.

Chroma refers to the intensity or purity of a color, but it doesn’t specifically denote the alteration of a color by adding gray or its complement. Shade refers to a color that has had black added to it, which darkens the color but does not address the graying process involving gray or its complement. Value pertains to the lightness or darkness of a color, rather than its saturation or dullness, which is the focus when discussing tones.