entail

In law, the settlement of land or other property on a successive line of people, usually succeeding generations of the original owner's family. An entail can be either general, in which case it simply descends to the heirs, or special, when it descends according to a specific arrangement - for example, to children by a named wife.

Entails are increasingly rare and the power to make them has often been destroyed by legislation - for example, restrictions in certain states of the USA. In England entails can be easily terminated.