Th-fronting

Th-fronting refers to the pronunciation of the English "th" as "f" or "v". When th-fronting is applied, /θ/ becomes /f/ (for example, three is pronounced as free) and /ð/ becomes /v/ (for example, bathe is pronounced as bave). Unlike the fronting of /θ/ to /f/, the fronting of /ð/ to /v/ usually does not occur word-initially (for example, while bathe can be pronounced as bave, that is rarely pronounced as *vat) although this was found in the speech of South-East London in a survey completed 1990-4. Th-fronting is a prominent feature of several dialects of English, notably Cockney, Estuary English, some West Country and Yorkshire dialects, Newfoundland English, African American Vernacular English, and Liberian English, as well as in many foreign accents (though the details differ among those accents).

A 2003 study found that th-fronting was most prevalent in and around the cities of London and Bristol. The first reference to "th"-fronting in London speech occurs in 1787. By 1850 it appears to have been considered a standard feature of working class speech in the city, and had the same status in Bristol by 1880. The use of the labiodental fricatives [f] and [v] for the dental fricatives [θ] and [ð] was noted in Yorkshire in 1876. In his 1892 book A Grammar of the Dialect of Windhill, Joseph Wright noted variable th-fronting in his district in words such as think, third and smithy.

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