Where does “язычество” come from?
язычество (Russian) comes from Russian язычник, from Old Church Slavonic ѩзꙑчьникъ, from Old Church Slavonic ѩзꙑкъ, 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.
язычество (Russian): paganism
Ancestry of “язычество”, step by step