the heir presumptive继承人
presumptive heir[法] 假定继承人
N（名词） a person who expects to succeed to an estate but whose right may be defeated by the birth of one nearer in blood to the ancestor 假定继承人; 期望能够继承某个产权的人，但其继承权可能会因存在另一人与先祖血缘更近而受挫 [property law] → compare heir apparent