Korean differs from English when referring to siblings. For instance with English, someone is brother or sister regardless of the person’s sex.
However with Korean, how you refer to your brother will depend on whether you are a man or a woman and your age. This is one of the very first things you will probably learn when you start learning Korean.
Women referring to their older brother: 오빠 (o-ppa)
This is also used in general for women referring to older males who are close to them or towards a boyfriend who is older. You have probably heard this one a lot in dramas.
Women referring to their younger brother: (남)동생
The 동생 means younger sibling, and adding 남 to it specifies that it’s her brother. However, this is usually omitted when talking about younger siblings.
Men referring to their older brother: 형 (hyeong)
Men also use this to refer to their close male friends who are older than them.
Men referring to their younger brother: (남) 동생
As you can see, this is the same as above.
As you can see, it’s quite different from how brother and sister is used in English. We will be covering sister in our next post