1Chiefly Law. Of a child: born after the father's death, or after the execution of the father's will. Also (Roman Law): born after the composition of the father's last will.

2Born later; born after another person, especially a sibling; younger.

Now usually in form afterborn. An after-born person or child. Also (treated as plural, usually with the): after-born people or children considered collectively. Now chiefly Law.