The Otomi (ˌoʊtəˈmiː; Otomí otoˈmi) are an indigenous people of Mexico inhabiting the central Mexican Plateau (Altiplano) region.
The Otomi are an indigenous people of the Americas who inhabit a discontinuous territory in central Mexico. They are linguistically related to the rest of the Otomanguean-speaking peoples, whose ancestors have occupied the Trans-Mexican Volcanic Belt for several thousand years. Currently, the Otomi inhabit a fragmented territory ranging from northern Guanajuato, to eastern Michoacán and southeastern Tlaxcala. However, most of them are concentrated in the states of Hidalgo, Mexico and Querétaro. According to the National Institute of Indigenous Peoples of Mexico, the Otomi ethnic group totaled 667,038 people in the Mexican Republic in 2015, making them the fifth largest indigenous people in the country. Of these, only a little more than half spoke Otomi. In this regard, it should be said that the Otomi language presents a high degree of internal diversification, so that speakers of one variety often have difficulty understanding those who speak another language. Hence, the names by which the Otomi call themselves are numerous: ñätho (Toluca Valley), hñähñu (Mezquital Valley), ñäñho (Santiago Mexquititlán in southern Querétaro) and ñ'yühü (Northern highlands of Puebla, Pahuatlán) are some of the names the Otomi use to refer to themselves in their own languages, although it is common that, when speaking in Spanish, they use the native Otomi, originating from the Nahuatl.
The word Otomi, is used to describe the larger Otomi ethnic group and the dialect continuum. From Spanish, the word Otomi has become entrenched in linguistic and anthropological literature. Among linguists, the suggestion has been made to change the academic designation from Otomi to Hñähñú, the endonym used by the Otomi of the Mezquital Valley, but no common endonym exists for all dialects of the language. Like most of the native names used to refer to the indigenous peoples of Mexico, the term Otomi is not native to the people to which it refers.