Where does “jězyk” come from?
jězyk (Lower Sorbian) comes from Proto-Slavic ęzykъ, from Proto-Balto-Slavic inźūˀ-kas, from Proto-Balto-Slavic *inźūˀs, from Proto-Balto-Slavic *dinźūˀs, from Proto-Indo-European dn̥ǵʰwéh₂s — tongue.
jězyk (Lower Sorbian): tongue
Ancestry of “jězyk”, step by step