pn A major language family which includes many of the native languages of Europe, Western Asia and India, with notable Indic, Iranian and European sub-branches.
n A member of the original ethnolinguistic group hypothesized to have spoken Proto-Indo-European and thus to have been the ancestor for most of India and Western Eurasia.
a Of or relating to the hypothetical parent language of the Indo-European language family. Also called Proto-Indo-European and abbreviated PIE.