ENIt is likely that at the end of the 16th or beginning of the 17th century, the Polish Tatars translated the Koran into the north-eastern variety of Polish. The original translation has not survived to our times. The basis of the research and the source of the excerpted vocabulary is therefore the Alytus Tefsir, i.e. the oldest (from 1723), full copy of the Tatar monument, the critical edition of which was prepared under an NPRH grant by researchers from the Centre for Kitabist Studies at the Nicolaus Copernicus University and their team. This article draws attention to the cultural phenomenon of the religious writing of the Polish Tatars, including tefsir. This writing links Islamic culture with the tradition of Muslim mysticism, shamanism and with the culture of Christianity, as well as with the folk beliefs and rituals of the peoples of the Grand Duchy of Lithuania: Polish, Lithuanian and Belorussian. The multiculturalism and multilingualism of tefsir can be shown at every level of the language: phoneticphonological, morphological, lexical-semantic and syntactic. Here, it is limited to lexical exponents of multiple cultures and languages. Keywords: Ethno linguistics, The Tatars of the Grand Duchy of Lithuania, Qur’an, tefsir, translation, lexis.