Grinding vs Pulverizing

If you 'pound' something you strike it repeatedly, for instance by hitting it with a hammer or a club. A stamping machine could also 'pound' something. If you 'grind' something, on the other hand, you apply fairly consistent pressure to the grinding tool and move it in such a way that the tool wears down the substance to be ground. Mill wheels 'grind' as does a pestle in a pestle and mortar.

The definitions of "pulverise" that you give include both "grind" and "pound". This shows that "grinding" and "pounding" are different processes which can contribute to the process of "pulverising" something so "pulverise" is a more general term incorporating both of the others. "Crushing" is another term which can include both "grinding" and "pounding" but can also include "squeezing' which means that it is not a true synonym of "pulverising".