The word Hñähñu [hɲɑ̃hɲṹ] has been proposed as an endonym, but since it represents the usage of a single dialect, it has not gained wide currency.

"[3] It is an exonym; the Otomi refer to their language as Hñähñú, Hñähño, Hñotho, Hñähü, Hñätho, Hyųhų, Yųhmų, Ñųhų, Ñǫthǫ, or Ñañhų, depending on the dialect.

It has been proposed that Proto-Otomi-Mazahua most likely was one of the languages spoken in Teotihuacan, the greatest Mesoamerican ceremonial center of the Classic period, the demise of which occurred ca.

This historical stage of the language was given Latin orthography and documented by Spanish friars who learned it in order to proselytize among the Otomi.

[12][13][14] In 1605, Alonso de Urbano wrote a trilingual Spanish-Nahuatl-Otomi dictionary, which included a small set of grammatical notes about Otomi.

Consequently, a significant number of Otomi documents exist from the period, both secular and religious, the most well-known of which are the Codices of Huichapan and Jilotepec.

[cn 4] In the late colonial period and after independence, indigenous groups no longer had separate status.

Coupled with a policy of castellanización this led to a rapid decline of speakers of all indigenous languages including Otomi, during the early 20th century.

[2] The highest concentration of speakers is found in the Valle de Mezquital region of Hidalgo and the southern portion of Querétaro.

[21] Because of recent migratory patterns, small populations of Otomi speakers can be found in new locations throughout Mexico and the United States.

SIL International's Ethnologue considers nine separate Otomi languages based on literature needs and the degree of mutual intelligibility between varieties.

Dialectologists tend to group the languages into three main groups that reflect historical relationships among the dialects: Northwestern Otomi spoken in the Mezquital Valley and surrounding areas of Hidalgo, Queretaro and Northern Mexico State, Southwestern Otomi spoken in the valley of Toluca, and Eastern Otomi spoken in the Highlands of Northern Puebla, Veracruz and Hidalgo, in Tlaxcala and two towns in the Toluca Valley, San Jerónimo Acazulco and Santiago Tilapa.

They concluded that Texcatepec, Eastern Highland Otomi, and Tenango may be considered the same language at a lower threshold of 70% intelligibility.

Ethnologue finds a similar lower level of 70% intelligibility between Querétaro, Mezquital, and Mexico State Otomi.

[14][cn 12] One variety of the Sierra dialect, that of San Gregorio, has been analyzed as having a fourth, falling tone.

Bernard's orthography has not been influential and in used only in the works published by himself and the Otomi author Jesus Salinas Pedraza.

[47][48] Practical orthographies used to promote Otomi literacy have been designed and published by the Instituto Lingüístico de Verano[cn 13] and later by the national institute for indigenous languages (INALI).

[49] This orthography has been adopted as official by the Otomi Language Academy centered in Ixmiquilpan, Hidalgo and is used on road signs in the Mezquital region and in publications in the Mezquital variety, such as the large 2004 SIL dictionary published by Hernández Cruz, Victoria Torquemada & Sinclair Crawford (2004).

A slightly modified version is used by Enrique Palancar in his grammar of the San Ildefonso Tultepec variety.

Proclitics differ from affixes mainly in their phonological characteristics; they are marked for tone and block nasal harmony.

[52][53] The standard orthography writes proclitics as separate words, whereas affixes are written joined to their host root.

Suffixes mark direct and indirect objects as well as clusivity (the distinction between inclusive and exclusive "we"), number, location and affective emphasis.

The categories of person of subject, tense, aspect, and mood are marked simultaneously with a formative which is either a verbal prefix or a proclitic depending on analysis.

[41][65] The dialects of Toluca and Ixtenco distinguish the present, preterit, perfect, imperfect, future, pluperfect, continuative, imperative, and two subjunctives.

mba-tųhų3/MVMT/IMPERF-singmba-tųhų3/MVMT/IMPERF-sing'he came singing'[68]When using nouns predicatively, the subject prefixes are simply added to the noun root: drʌ-mǒkhá1SG/PRES/CONT-priestdrʌ-mǒkhá1SG/PRES/CONT-priest'I am a priest'[68]Transitive verbs are inflected for agreement with their objects by means of suffixes, while using the same subject prefixes as the intransitive verbs to agree with their agents.

Often such intransitive verbs are stative, i.e. describing a state, which has prompted the interpretation that morphosyntactic alignment in Otomi is split between active–stative and accusative systems.

The fact that roots in the latter group encode the patient/subject of the predicate using the same suffixes as transitive verbs use to encode the patient/object has been interpreted as a trait of Split intransitivity,[65] and is apparent in all Otomi dialects; but which specific stative verbs take the object prefixes and the number of prefixes they take varies between dialects.

It has been suggested that some Otomi dialects are shifting from a verb-initial to a subject-initial basic word order under the influence of Spanish.

The religious tradition of songs, with Spanish lyrics, dates to the 16th century, when missionaries such as Pedro de Gante taught Indians how to construct European style instruments to be used for singing hymns.

The following example of an Otomi song about the brevity of life was recollected by Ángel María Garibay K. in the mid-twentieth century:[cn 18]