Castúo is the generic name for the dialects of Spanish spoken in the autonomous community of Extremadura, in Spain. It is not to be confused with Extremaduran, a language between Asturleonese and Castilian, or with Fala, another language spoken in Extremadura that is most similar to Galician-Portuguese.

APLEx Association for the study and divulgation of Extremaduran linguistic patrimony