So, you want to know how do you say sister in Korean. Simple, right? You look it up in a dictionary, find a word, and start using it.
Except, if you do that, you are probably going to offend someone. Or at the very least, look very, very confused.
Korean isn't like English. In English, a sister is a sister. She’s your sibling. Whether she's older, younger, or your best friend, the label stays pretty stagnant. In Korea? The language is a social map. It tells everyone exactly where you stand in the hierarchy. It's about age. It's about gender. It's about whether you are a man or a woman speaking.
If you get it wrong, you aren't just making a typo. You are breaking a social contract.
The Gender Divide: Why Your Gender Matters
This is the part that trips up most beginners. To figure out the right way to say sister, you first have to look in the mirror. Are you a guy? Or are you a girl?
If you are a male and you’re talking about your older sister, you use the word Nuna (누나). It’s an iconic word. You’ve probably heard it in K-Dramas where a younger guy is pining after an older woman. But in its purest sense, it’s just "older sister" for boys.
Now, if you are female, that word is useless to you. Completely. You would never call your older sister Nuna. Instead, you say Unnie (언니).
It sounds different. It feels different. Unnie carries a vibe of "cool older girl mentor." You’ll hear girls calling their older female friends Unnie all the time in Seoul cafes. It’s a term of endearment, but it’s also a sign of respect.
What About the Little Sisters?
Interestingly, the gender of the speaker stops mattering once we talk about younger sisters. The hierarchy only looks upward. When you look down at someone younger than you, the language levels out.
The general word for a younger sibling is Dongsaeng (동생). To make it specific to a sister, you just add the prefix for "female," which is yeo (여). So, Yeodongsaeng (여동생).
But here is the catch: most Koreans don't actually call their younger sister "Yeodongsaeng" to her face. That would be weird. It’s like turning to your sibling and saying, "Hello, Younger Female Sibling." Instead, they just use their name. Or they call them "Ya!" (which is basically "Hey!").
The Social Nuance of Nuna and Unnie
You can't talk about how do you say sister in Korean without talking about friendship. In Western culture, if you meet a girl who is one year older than you, you’re just friends. You’re peers.
In Korea, that one-year gap is a mountain.
If she is 22 and you are 21, she is your Unnie (if you’re a girl) or your Nuna (if you’re a guy). You don't call her by her first name. Ever. Not unless you want her to think you’re incredibly rude or trying to start a fight. Using these "sister" terms for non-relatives is the glue of Korean society. It creates a "pseudo-family" structure.
It’s about intimacy. When a guy calls a female friend Nuna, he’s acknowledging she has more life experience. When a girl calls a stranger Unnie—maybe a shopkeeper or a waitress—she’s being friendly and polite.
But be careful.
If you call a woman who is significantly older than you Unnie, and she thinks she looks much older, she might get offended. She might prefer Imo (auntie) or Ajumma (middle-aged lady). It is a minefield. Honestly, it's a miracle anyone communicates at all.
Honorifics and the "Formal" Sister
We’ve covered the casual/polite terms. But what if you are in a formal setting? What if you are introducing your sister to your boss?
You wouldn't just say "This is my Unnie." You’d use more formal terminology.
The word Jamae (자매) refers to "sisters" as a collective noun. You see this in news reports or formal documents. If a journalist is talking about two sisters who won a marathon, they use Jamae.
Then there’s the term Nui (누이). This is a bit old-school. It’s a poetic, slightly dated way for a man to refer to his sisters (older or younger). You’ll find it in literature or old folk songs. You probably won't use it at a BBQ in Hongdae, but knowing it exists gives you that "expert" edge.
The Honorific Suffix: -nim
If you want to be extra respectful—maybe you’re talking about someone else’s older sister—you add -nim (님).
- Nunanim (누나님)
- Unnim (언니님) - though this is less common than Nunanim.
Adding -nim is like putting a tuxedo on the word. It’s very formal.
Common Mistakes People Make
Most learners fail because they try to translate English thoughts into Korean words.
Don't do that.
Mistake #1: Using "Sister" for yourself.
If someone asks if you have siblings, don't say "I am a Nuna." You would say "I have a younger brother" or "I am the eldest." The title is something others give you, or something you use to address others.
Mistake #2: Forgetting the age gap.
If you are 25 and your sister is 24, she is your Yeodongsaeng. If she is 26, she is your Unnie or Nuna. There is no "middle ground" where you are just "sisters" without an age-based label.
Mistake #3: Overusing the word.
In English, we might say, "Hey sister, can you pass the salt?" In Korean, once the relationship is established, you often drop the subject entirely. The context does the heavy lifting.
Why This Matters for Learners
Understanding how do you say sister in Korean is basically a crash course in Confucianism. The language is built on the idea that everyone has a place. Respect flows upward; care flows downward.
When you call someone Unnie, you are saying, "I trust you to lead." When you call someone Nuna, you are saying, "I respect your seniority."
It’s not just vocabulary. It’s a worldview.
If you’re watching a show like Little Women (the Korean drama version), pay attention to how the sisters address each other. The middle sister doesn't call the oldest sister by name. She says Unnie. Even when they are screaming at each other. Even in a heated argument, the hierarchy usually holds firm. It's that deeply ingrained.
How to Practice Using These Terms
The best way to get comfortable isn't by staring at a textbook. It's by observing.
- Watch Variety Shows: Shows like Running Man or I Live Alone are goldmines. You’ll hear celebrities navigating these titles in real-time. Notice when a male guest calls a female cast member Nuna to butter her up.
- Check the Age: Before you meet a Korean person, or if you're talking about characters, find out their birth year. Everything starts with the birth year.
- Listen for the Tone: Unnie can be whined, it can be whispered, or it can be shouted. The meaning changes with the pitch.
A Quick Cheat Sheet for Reference
Forget the fancy tables. Here is the raw breakdown:
- Older sister (if you are a man): Nuna.
- Older sister (if you are a woman): Unnie.
- Younger sister (anyone): Yeodongsaeng.
- Sisters (as a group/category): Jamae.
- Polite/Formal older sister: Nunanim.
It feels like a lot. But honestly, once you start using it, it becomes second nature. You’ll find yourself wanting to call your older female friends "Unnie" even when you're speaking English because there just isn't a perfect English equivalent that captures that specific blend of respect and intimacy.
Next Steps for Mastering Korean Family Titles
Now that you've got sisters down, you should probably look into the brother side of things. It's just as split. Boys have Hyung, girls have Oppa. And yes, Oppa has its own massive set of cultural baggage that you definitely need to understand before you go using it at a K-pop concert.
The most practical thing you can do right now is grab a notebook and list the women in your life who are older than you. If you were speaking Korean to them, which ones would be your Unnie? Which ones would be your Nuna? Categorizing your real-world relationships helps the vocabulary stick better than any flashcard ever could.
Once you've mastered the sibling titles, move on to Seonbae (senior) and Hubae (junior). These are the workplace versions of the sister/brother dynamic. They follow similar rules but apply to your boss, your coworkers, or your classmates. Mastering these is how you truly go from "someone who knows some Korean words" to "someone who understands Korean culture."