Pro·to-In·do-Eur·o·pe·an 
(prō′tō-ĭn′dō-yr′ə-pēən) Abbr. PIE
(prō′tō-ĭn′dō-yr′ə-pēən) Abbr. PIEn.
The reconstructed language that was the ancestor of the Indo-European languages.
adj.
Of, relating to, or being Proto-Indo-European or one of its reconstructed linguistic features.