“Egyptians would not eat with Hebrews”
They ate separately because the Egyptians would not eat with the Hebrews, since that was detestable to them. (Genesis 43:32 BSB)
What it sounds like today
An awkward seating arrangement at a formal dinner.
The cultural key
Egyptian culture drew hard lines of ritual purity and ethnic separation, and sharing a table with foreigners, especially Semitic herdsmen, was considered defiling. The word is to'evah, 'abomination,' the same strong term the Egyptians would later apply to shepherds (46:34). The detail is quietly ironic: the man they are forbidden to eat with is Joseph, an Egyptianized Hebrew who now controls their food supply, seated apart from the very brothers who once refused to sit and eat with him before selling him.
Recovered meaning
A minor note about seating carries the story's deep irony: the Hebrews are too 'detestable' to share Egypt's table, yet a Hebrew now holds the whole nation's bread. The boundary meant to exclude Joseph's people bends around the brother they cast out.