Definition of entails:
(v) :
(transitive) To imply, require, or invoke.
(v) :
(transitive) To settle or fix inalienably on a person or thing, or on a person and his descendants or a certain line of descendants; -- said especially of an estate; to bestow as a heritage.
(n) :
That which is entailed.
(n) :
An estate in fee entailed, or limited in descent to a particular class of issue.
(n) :
The rule by which the descent is fixed.
(v) :
(transitive, obsolete) To appoint hereditary possessor.