Heir apparent

The term is also applied metaphorically to an expected successor to any position of power, e.g. a political or corporate leader.

In a hereditary system governed by some form of primogeniture, an heir apparent is easily identifiable as the person whose position as first in the line of succession to a title or office is secure, regardless of future births.

An heir presumptive, by contrast, can always be "bumped down" in the succession by the birth of somebody more closely related in a legal sense (according to that form of primogeniture) to the current title-holder.

The clearest example occurs in the case of a childless bearer of a hereditary title that can only be inherited by one person.

Indeed, when Queen Victoria succeeded her uncle King William IV, the wording of the proclamation even gave as a caveat: ...saving the rights of any issue of his late Majesty King William IV, which may be born of his late Majesty's consort.This provided for the possibility that William's wife, Adelaide of Saxe-Meiningen, was pregnant at the moment of his death, since such a posthumous child, regardless of its sex, would have displaced Victoria from the throne.

Daughters (and their lines) may inherit titles that descend according to male-preference primogeniture, but only in default of sons (and their heirs).

As succession to titles, positions, or offices in the past most often favoured males, females considered to be an heir apparent were rare.

Victoria was not heir apparent from birth (in 1977), but gained the status in 1980 following a change in the Swedish Act of Succession.