Many languages do not distinguish between what in English are described as "blue" and "green". They instead use a cover term spanning both. When the issue is discussed in linguistics, this cover term is sometimes called grue in English. 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...