Cyan is any of the colors in the blue-green range of the visible spectrum, i.e., between approximately 490 and 520 nm. It is considered one of the main subtractive primary colors. Cyan is sometimes considered green or blue because of the way it appears.

Cyan (/ ˈsaɪ.ən, - æn /) is the color between green and blue on the visible spectrum of light. It is evoked by light with a predominant wavelength between 490 and 520 nm, between the wavelengths of green and blue.

The color cyan, a greenish-blue, has notable tints and shades. It is one of the subtractive primary colorsalong with magenta, and yellow. The first recorded use of cyan blueas a color name was in 1879 ("cyan blue" being the name used for "cyan" in the 19th century).

Cyan ➦ A vibrant pale greenish-blue colour between blue and green in the visible spectrum; the complementary colour of red; the colour obtained by subtracting red from white light.