Pro·to-In·do-Eu·ro·pe·an
noun/ˌprəʊtəʊ ˌɪndəʊ ˌjʊərəˈpiːən/
/ˌprəʊtəʊ ˌɪndəʊ ˌjʊrəˈpiːən/
[uncountable]- the ancient language on which all Indo-European languages are thought to be based. There are no written records of Proto-Indo-European, but experts have tried to construct it from the evidence of modern languages.
原始印欧语（据信为所有印欧语言之源头）