jaadu (Ingrian) comes from Russian яд, from Old East Slavic ѣдъ, from Proto-Slavic ědъ, from Proto-Slavic ěsti, from Proto-Balto-Slavic ēˀstei, from Proto-Indo-European h₁édti, from Proto-Indo-European h₁ed- — to eat.
jaadu (Ingrian): poison