From Proto-Slavic *čȃrъ, čȃrь (Russian ча́ры (čáry), Polish czar), from Proto-Indo-European *kʷer- (“to do, make, build”) (Sanskrit करोति (karóti), Lithuanian kùrti). Slavic forms with čar- (compare čárati) presuppose a nominal lengthened-grade derivation, i.e. Proto-Balto-Slavic *kēr- (Lithuanian kẽras (“charm, magic”)). Serbo-Croatian i-stem is probably an archaism - lengthened grade is expected in PIE root nouns which yield Balto-Slavic i-stems. PIE root probably already had magical connotations, i.e. denoting remote action by magical means. First attested in the 16th century.
čȃr m (Cyrillic spelling ча̑р)