The term ethnotaxonomy refers either to that subdiscipline within ethnology which studies the taxonomic systems defined and used by individual ethnic groups, or to the operative individual taxonomy itself, which is the object of the ethnologist's immediate study. For example, in many West African languages, the perceptual world of color is classified into the principal categories "Red," "White," and "Black" (finer gradations being secondary). The range of wavelengths that an English-speaker calls blue would be a subcategory of "Black."