Where does “моллюск” come from?
моллюск (Russian) comes from French mollusque, from New Latin Mollusca, from Latin molluscus, from Latin mollis, from Latin molduis, from Proto-Italic moldus, from Proto-Indo-European *ml̥dus, from Proto-Indo-European (s)meld- — to soften, to melt.
моллюск (Russian): mollusc
Ancestry of “моллюск”, step by step