Definition - A hypothetical parent language from which a language family's dialects and languages have been derived.

Example -
Proto-Indo-European, Proto-Bantu, and Proto-Uralic.

Etymology -
The word derives from the German Ur, original or primitive + Sprache, language.

Oxford English Dictionary -
Its first citation is from 1908:
"The Semitic Ursprache (or common parent)."
(T. G. Tucker, Introd. Nat. Hist. Lang. ix. 163)

Quotation -
"Greek, Latin and Sanskrit … are all close enough in structure to their common progenitor, the Ursprache, to have retained the Ursprache's principal characteristic."
(Source: A. Toynbee Greeks & their Heritages (1981), page 122)

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