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In many languages, the colors described in English as "blue" and "green" are colexified, i.e., expressed using a single umbrella term.

The exact definition of "blue" and "green" may be complicated by the speakers not primarily distinguishing the hue, but using terms that describe other color components such as saturation and luminosity, or other properties of the object being described. For example, "blue" and "green" might be distinguished, but a single term might be used for both if the color is dark. Furthermore, green might be associated with yellow, and blue with either black or gray.