One who inherits, or is entitled to succeed to the possession of, any property after the death of its owner; one on whom the law bestows the title or property of another at the death of the latter.
I am my father's heir and only son.
One who receives any endowment from an ancestor or relation; as, the heir of one's reputation or virtues.
one who, after his ancector's death, has a right to inherit all his intestate estate.
Heir presumptive
one who, if the ancestor should die immediately, would be his heir, but whose right to the inheritance may be defeated by the birth of a nearer relative, or by some other contingency.