In this article I develop an exercise of conceptual history about the word 'piuco', which has diverse uses recorded in the nineteenth and twentieth centuries. I reflect on the origin, fields of experience and expectatives concentrated in some uses of the concept 'piuco' during the years of the War of the Pacific: a potential demonym, constructed on the basis of his identification with the popular classes of the Chiloe province. It is a concept in the center of the racial discourses, And I relate his trajectory and diverse meanings, both pragmatic and ideological, with the most important process in the nineteenth century history of Chile and Chiloe. Some answers are considered about the possible causes of the frustration of the concept 'piuco' as a demonym equivalent of the current word 'chilote'. The text is based on a revision of differential dictionaries, publications on geography, politics and travels, newspapers of Chiloe and part of the letters of the Intendent Luis Martiniano Rodriguez.