One of the subtractive primary colors—appearing blue-green—characterized by its absorption of red light. It is used in various proportions with the other subtractive primaries—magenta and yellow—to form many other colors. Cyan is often incorrectly used as a synonym for blue.
'Cyan is also a term for one of the four process color inks used in process color printing. Also incorrectly referred to as "blue," perhaps because the word cyaneous refers to a deep, cerulean blue, while its etymological root, the Greek word kyanos, means "deep blue." Cyan is the blue component used in many types of color mixing, and is also a secondary color in additive color theory produced by the mixing of red and blue.