Proto-language

In the tree model of historical linguistics, a proto-language is a postulated ancestral language from which a number of attested languages are believed to have descended by evolution, forming a language family. Proto-languages are usually unattested, or partially attested at best. They are reconstructed by way of the comparative method.^[1]

In the family tree metaphor, a proto-language can be called a mother language. Occasionally, the German term Ursprache (pronounced [ˈuːɐ̯ʃpʁaːxə] ^ⓘ; from ur- 'primordial', 'original' + Sprache 'language') is used instead. It is also sometimes called the common or primitive form of a language (e.g. Common Germanic, Primitive Norse).^[1]

In the strict sense, a proto-language is the most recent common ancestor of a language family, immediately before the family started to diverge into the attested daughter languages. It is therefore equivalent with the ancestral language or parental language of a language family.^[2]

Moreover, a group of lects that are not considered separate languages, such as the members of a dialect cluster, may also be described as descending from a unitary proto-language.

^ ^a ^b Campbell, Lyle (2007). Glossary of Historical Linguistics. Edinburgh University Press. pp. 158–159. ISBN 978-0-7486-3019-6.
^ Rowe, Bruce M.; Levine, Diane P. (2015). A Concise Introduction to Linguistics. Routledge. pp. 340–341. ISBN 978-1-317-34928-0. Retrieved 26 January 2017.

[:0-1] Campbell, Lyle (2007). Glossary of Historical Linguistics. Edinburgh University Press. pp. 158–159. ISBN 978-0-7486-3019-6.

[2] Rowe, Bruce M.; Levine, Diane P. (2015). A Concise Introduction to Linguistics. Routledge. pp. 340–341. ISBN 978-1-317-34928-0. Retrieved 26 January 2017.

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