What is the meaning of the word "shell"?

Definitions:

a rigid covering that envelops an object noun
- the satellite is covered with a smooth shell of ice
a very light narrow racing boat noun
- The regatta had at least one shell from all the local schools.
fall out of the pod or husk verb
- The corn shelled
hit the pitches of hard and regularly verb
- The visiting team shelled the pitcher for eight runs in the first inning.
remove from its shell or outer covering verb
- shell the legumes
use explosives on verb
- The enemy has been shelling us all day