“ Heir by custom, or customary heir, he who inherits by a particular and local custom, as in borough-English, whereby the youngest son inherits, or in gavelkind, whereby all the sons inherit as parceners, and made but one heir. ”

“ Heir general, or heir at law, he who after the death of his ancestor has, by law, the right to the inheritance.
Heir presumptive, one who is next in succession, but whose right is defeasible by the birth of a nearer heir, e.g. a brother or nephew, whose presumptive right may be destroyed by the birth of a child, or a daughter, whose right may be defeated by the birth of a son. ”