reversion

noun

• 1a return to a previous state, practice, or belief:there was some reversion to polytheism a reversion to the two-party system
• Biology the action of reverting to a former or ancestral type.

• 2 Law the right, especially of the original owner or their heirs, to possess or succeed to property on the death of the present possessor or at the end of a lease:the reversion of property
• a property to which someone has the right of reversion.
• the right of succession to an office or post after the death or retirement of the holder:he was given a promise of the reversion of Boraston’s job