🔼The name Ammon in the Bible
After the destruction of Sodom, where they used to live, the two daughters of Lot are worried that they will remain childless. And so they concoct the plan of boozing up their father and mating with him when he is passed out. The plan works. Without Lot ever realizing what goes on, the older sister becomes pregnant and gives birth to a boy she names Moab. He will be the father of the Moabites. The younger sister becomes pregnant and gives birth to Ben-ammi. He will be the father of "the sons of Ammon".
The story does not tell how Lot explained to himself the pregnancy of his two daughters without there being any other men around.
🔼Etymology of the name Ammon
The name Ammon derives of the assumed root עמם:
The ון upon which the name Ammon ends is a common construction to localize or personify the root.
For a meaning of the name Ammon, NOBSE Study Bible Name List reads A People. Jones' Dictionary of Old Testament Proper Names proposes Great People, taking the ון extension as an intensitive. BDB Theological Dictionary doesn't translate the name Ammon, but refers to the noun עם, meaning kinsman.