Someone told me: "Here 'earth' means 'cave'. 'Man from earth' means 'caveman'."
I doubt that. I can't find any dictionary supporting that explanation.
However, the word "earth" does have multiple meanings, such as "the planet Earth" and "mud, soil". I wonder which one is the most suitable here.
Some points I notice:
Here "Earth" is capitalised, but nouns in titles are always capitalised, so it does not mean "Earth" must refer to "the planet Earth".
Besides, there is no "the" before "Earth". For which meaning(s) can the article before "earth" be dropped?
The "soil/mud" meaning is explainable. A cave can be made from soil, though I always thought cavemen lived in stone cave.
If "Earth" does mean "the planet Earth", what is the meaning of this title? Everyone is from the planet Earth.