Substratum in Vedic Sanskrit

Vedic has a number of linguistic features which are alien to most other Indo-European languages. Prominent examples include: phonologically, the introduction of retroflexes, which alternate with dentals; morphologically, the formation of gerunds; and syntactically, the use of a quotative marker (iti). Philologists attribute such features, as well as the presence of non-Indo-European vocabulary, to a local substratum of languages encountered by Indo-Aryan peoples in Central Asia and within the Indian subcontinent, including the Dravidian languages.

Scholars have identified a substantial body of loanwords in the earliest Indian texts, including clear evidence of Non-Indo-Aryan elements (such as -s- following -u- in Rigvedic busa). While some loanwords are from Dravidian, and other forms are traceable to Munda or Proto-Burushaski, the bulk have no sensible basis in any of these families, suggesting a source in one or more lost languages. The discovery that some loan words from one of these lost sources had also been preserved in the earliest Iranian texts, and also in , convinced Michael Witzel and Alexander Lubotsky that the source lay in Central Asia and could be associated with the Bactria–Margiana Archaeological Complex (BMAC). Another lost language is that of the Indus Valley Civilization, which Witzel initially labelled Para-Munda, but later the Kubhā-Vipāś substrate.

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