Each of two or more female heirs who jointly inherit in default of a male heir; (also) the son or male representative of such an heir; similarly "heiress portioner".
Origin
Late 16th century.
Definition of heir portioner in US English:
heir portioner
noun
Each of two or more female heirs who jointly inherit in default of a male heir; (also) the son or male representative of such an heir; similarly "heiress portioner".