to be an outsider: to stand on the wrong side of a line that matters here, whether a circle, a household, a nation, the covenant, or holy space
This word does not name a fixed kind of person. It marks a position. The same word covers a layman standing next to a priest, an enemy army standing on Israel's land, an idol standing where the LORD belongs, another man's wife standing in place of one's own, and even a person who has become strange inside his own house. In each case the word says one thing: this one is outside the circle that counts right here.
The context, not the word, tells you which line is in view. That is why the word can do priestly law, prophetic warning, love poetry, and wisdom teaching with the same three letters. The senses below are the different circles the word draws a line around, not different words. The core idea, a turning aside out of place, is what they all share.
Most English Bibles flatten this into "stranger" or "foreigner," which makes the word sound like it always means a person from another nation. It does not. In the laws about the sanctuary the outsider is usually an ordinary Israelite who simply is not a priest. The word is about access and belonging, not about nationality.