T–V distinction

In sociolinguistics, a T–V distinction (from the Latin pronouns tu and vos) is a contrast, within one language, between various forms of addressing one's conversation partner or partners that are specialized for varying levels of politeness, social distance, courtesy, familiarity, age or insult toward the addressee. Languages such as modern English that, outside of certain dialects, have no morphosyntactic T–V distinction may have semantic analogues to convey the mentioned attitudes towards the addressee, such as whether to address someone by given or surname, or whether to use sir/ma'am. Under a broader classification, T and V forms are examples of honorifics.

The terms T and V, based on the Latin pronouns tu and vos, were first used in a paper by the social psychologist Roger Brown and the Shakespearian scholar Albert Gilman. This was a historical and contemporary survey of the uses of pronouns of address, seen as semantic markers of social relationships between individuals. The study considered mainly French, Italian, Spanish and German. The paper was highly influential and with few exceptions, the terms T and V have been used in subsequent studies.

In Latin, tu was originally the singular, and vos the plural, with no distinction for honorific or familiar. According to Brown and Gilman, usage of the plural to the Roman emperor began in the fourth century AD. They mention the possibility that this was because there were two emperors at that time (in Constantinople and Rome), but also mention that "plurality is a very old and ubiquitous metaphor for power". This usage was extended to other powerful figures, such as Pope Gregory I (590–604). However, Brown and Gilman note that it was only between the twelfth and fourteenth centuries that the norms for the use of T- and V-forms crystallized. Less commonly, the use of the plural may be extended to other persons, such as the "royal we" (majestic plural) in English.

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