Why do we put ress at the end of some words, like actress, mayoress and murderess, but not for others like doctress, accountantress, or teacheress?

Question

Why do we put ress at the end of some words, like actress, mayoress and murderess, but not for others like doctress, accountantress, or teacheress?

In: 12609

Answer 1

Older forms of English kept Latin’s gender-specific suffixes -tor and -trix; tor is for males and trix is for females. A male pilot is an aviator and a female pilot is an aviatrix. A male fighter is a gladiator and a female fighter is a gladiatrix.

This contrasts with the modern system where tor is generally used for both men and women, and trix are for kids.