The high variety may be an older stage of the same language (as in medieval Europe, where Latin (H) remained in formal use even as colloquial speech (L) diverged), an unrelated language, or a distinct yet closely related present-day dialect (as in northern India and Pakistan, where Hindustani (L) is used alongside the standard registers of Hindi (H) and Urdu (H); Germany, where Hochdeutsch (H) is used alongside German dialects (L); the Arab world, where Modern Standard Arabic (H) is used alongside other varieties of Arabic (L); and China, where Standard Chinese (H) is used as the official, literary standard and local varieties of Chinese (L) are used in everyday communication).
The term was quickly adapted into French as diglossie by the Greek linguist and demoticist Ioannis Psycharis, with credit to Rhoides.
[11] In his 1959 article, Charles A. Ferguson defines diglossia as follows: DIGLOSSIA is a relatively stable language situation in which, in addition to the primary dialects of the language (which may include a standard or regional standards), there is a very divergent, highly codified (often grammatically more complex) superposed variety, the vehicle of a large and respected body of written literature, either of an earlier period or in another speech community, which is learned largely by formal education and is used for most written and formal spoken purposes but is not used by any sector of the community for ordinary conversation.
Ferguson gives the example of standardized Arabic and says that, "very often, educated Arabs will maintain they never use L at all, in spite of the fact that direct observation shows that they use it constantly in ordinary conversation" [4] Joshua Fishman expanded the definition of diglossia to include the use of unrelated languages as high and low varieties.
"[14] Code-switching is also commonplace, especially in the Arabic world; according to Andrew Freeman, this is "different from Ferguson's description of diglossia which states that the two forms are in complementary distribution.
In Asia, the Philippines is the biggest example of such colonial exoglossia, with English since the Spanish-American War of 1898, Spanish before then (with a historic presence in place names, personal names, and loanwords in the local languages) and local Austronesian Philippine languages used for everyday situations; Timor-Leste is in a similar situation with Portuguese.
[19] Among Garifuna (Karif) speakers in Central America, men and women often have different words for the same concepts.
Lack of contact between the two groups led to the development of gender-specific varieties of Irish Sign Language.
Children often learn colloquial (regionalized) Arabic through immersion, with MSA being later taught formally in school.
[24] Greek diglossia belongs to the category whereby, while the living language of the area evolves and changes as time passes by, there is an artificial retrospection to and imitation of earlier (more ancient) linguistic forms preserved in writing and considered to be scholarly and classic.
The phenomenon, called "Atticism", dominated the writings of part of the Hellenistic period, the Byzantine and Medieval era.
Katharevousa did not constitute the natural development of the language of the people, the "Koine", "Romeika", Demotic Greek or "Dimotiki" as it is currently referred to.
The Singaporean government has long insisted that English be the sole language used, both in formal settings and everyday life.
[28] As an aspect of study of the relationships between codes and social structure, diglossia is an important concept in the field of sociolinguistics.
In many cases of diglossia, the two dialects are so divergent that they are distinct languages as defined by linguists: they are not mutually intelligible.
Thomas Ricento, an author on language policy and political theory believes that there is always a "socially constructed hierarchy, indexed from low to high.
"[29] The hierarchy is generally imposed by leading political figures or popular media and is sometimes not the native language of that particular region.
Thus in those diglossic societies which are also characterized by extreme inequality of social classes, most people are not proficient in speaking the high dialect, and if the high dialect is grammatically different enough, as in the case of Arabic diglossia, these uneducated classes cannot understand most of the public speeches that they might hear on television and radio.
In many diglossic areas, there is controversy and polarization of opinions of native speakers regarding the relationship between the two dialects and their respective statuses.