In the Odyssey, Odysseus is sometimes addressed as διογενής "Zeus-born". For example, 11.60:
διογενὲς Λαερτιάδη, πολυμήχαν' Ὀδυσσεῦ
O Zeus-born son of Laërtes, Odysseus of many tricks…
Clearly the meaning isn't that he's literally a son of Zeus, since his father is named in the same line. And L&S gives an alternative, that it simply means he's "ordained and upheld by Zeus".
But I'm curious where this secondary meaning came from. The word seems to be very transparently from the roots of Ζεύς + γόνος, from PIE *ǵenh₁- "give birth to".
Do we know how this "ordained" usage arose? Is this another meaning of γόνος that we see in other formations? Or is it a peculiarity of this particular word?