What is the difference between 도련님 and 서방님?

ANSWER: Both words are used by married women in Korea to refer to or to address the younger brothers of their husbands. The difference between the two is that if the younger brother of the husband is unmarried, the wife of the older brother addresses the younger brother as 도련님, but if he is married, then she addresses him as 서방님. In the past, Korean women also addressed their husbands as 서방님 and may still do so in a joking way.

Titles and forms of address are very important in Korea, but it seems that Koreans are starting to get a little uncomfortable with some of them, especially Korean women, who wonder why Korean men are shown more respect when they are addressed than Korean women.

In Korea, 처 (妻) means "wife," and 부 (夫) means "husband," so Korean women are starting to wonder why they have to address their husbands' younger brothers as 도련님 and 서방님 while the husbands get to address the younger brothers of their wives as simply 처남 (妻男), which can refer to either a married younger brother or an unmarried younger brother. And the honorific 님 does not have to be attached to 처남.

So, more and more Korean women are asking, "Why can't I just address my husband's younger brother as 부남 (夫男), whether he is married or not, since my husband gets to address my younger brother as 처남 (妻男)?" Personally, I think that is a good question.