Where does “языкознание” come from?
языкознание (Russian) comes from Russian язы́к, from Old East Slavic ѧзꙑкъ, 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.
языкознание (Russian): linguistics
Ancestry of “языкознание”, step by step