'Heir' in the Bible

But Abram said, “Lord God, what can You give me, since I am childless and the heir of my house is Eliezer of Damascus?”

Abram continued, “Look, You have given me no offspring, so a slave born in my house will be my heir.”

Now the word of the Lord came to him: “This one will not be your heir; instead, one who comes from your own body will be your heir.”

So she said to Abraham, “Drive out this slave with her son, for the son of this slave will not be a coheir with my son Isaac!”