What you’ll notice about Korean vocabulary related to the family is that there may be more than one way to address someone depending on your rank, age, and relation to the person. Shall we take a look?

아버지 – father (polite)

아버님 – father (very polite)

아빠 – dad (informal)

어머니 – mother (polite)

어머님 – mother (very polite)

엄마 – mom (informal)

I just want to include a side note here by saying that there are some children who call their father and mother by the polite terminology 아버지/아버님 and 어머니/어머님. The majority of Koreans tend to use the informal terminology 엄마 and 아빠. Using 엄마 and 아빠 doesn’t necessarily mean that the children are being rude to their parents. Using 엄마 and 아빠 could be a sign that the children are very close to their parents, so close that the formality has been dropped. It really depends upon the person, but when a child calls his parents 아버지 and 어머니, this could be an indication that the child is not very close to his parents. However, it could also be that some families are just more formal.

부모 – parents

부모님 – parents (honorific)

할아버지 – grandfather

할아버님 – grandfather (honorific)

할머니 – grandmother

할머님 – grandmother (honorific)

조부모 – grandparents

조부모님 – grandparents (honorific)

Did you notice that just by adding 님 to the title makes the word honorific? For example, 조부모 versus 조부모님 both mean grandparents, but the second one is much more polite. Also, some people address other elderly people not biologically related to them as 할머니 or 할아버지. This is because it would be rude to address an elderly person by their name as well as addressing them as “you”, so the only alternative is to call the person 할머니 or 할아버지.