Dongsaeng

Oppa 오빠

The word a woman or girl uses for her older brother — and, by extension, for any older male she feels close to, including older male friends and boyfriends. Only female speakers use it; a man addressing an older man says "hyung" instead. Because it signals warmth and closeness, calling a non-relative "oppa" carries a flirtatious or affectionate undertone.

Unnie 언니

What a woman or girl calls her older sister, or an older female friend she's close to. It's strictly for female speakers; a man addressing an older woman says "noona" instead. It conveys affection and a sister-like bond rather than formality.

Hyung 형

What a man or boy calls his older brother, or an older male friend he's close to. It's for male speakers only; women use "oppa" for older males. Adding -nim ("hyungnim") makes it more deferential — or, in crime dramas, is how gang members address the boss.

Noona 누나

What a man or boy calls his older sister, or an older female friend he's close to. It's for male speakers only; women say "unnie" for older women. Like "oppa," it can carry romantic potential when used toward a non-relative.

Sunbae 선배

A senior at your school, workplace, or industry — someone who entered before you, regardless of their actual age. Both men and women use it, usually with the honorific suffix as "sunbaenim." The junior counterpart is "hoobae."

Hoobae 후배

A junior at your school, workplace, or industry — someone who entered after you, regardless of age. It's mostly used to describe the relationship rather than to address someone: you'd say "she's my hoobae," but call the person by their name. The senior counterpart is "sunbae."