When I touch a dead body, it feels more 'solid' than a living body. This raises the question: Is the living body a hollow vessel? And what happens when death takes over this hollow body?

Hollow means: empty, lacking, missing, absent. The word hollow is connected to a place: a hollow place or hole. The noun sense of lowland, valley or basin.
Dictionary.com says:
1. Having a space or cavity inside; not solid; empty: a hollow sphere.
2. Having a depression or concavity: a hollow surface.
3. Sunken, as the cheeks or eyes.
4. (Of sound) not resonant; dull, muffled, or deep: a hollow voice.
5. Without real or significant worth; meaningless: a hollow victory.
6. Insincere or false: hollow compliments.
7. Hungry; having an empty feeling: I feel absolutely hollow, so let's eat.
8. An empty space within anything; a hole, depression, or cavity.
9. A valley: they took the sheep to graze in the hollow.
10. Foundry. A concavity connecting two surfaces otherwise intersecting at an obtuse angle.

Could the living hollow body be missing something, which will be filled in when death takes over? What could that be?

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