Oppa -

If you want to dive deeper into Korean social etiquette, I can provide more details on: (how to address bosses and juniors)

The term has gained global recognition through Hallyu (the Korean Wave): If you want to dive deeper into Korean

It is typically reserved for men who are 1 to 10 years older than the speaker. For men significantly older (such as those in their 40s or 50s), terms like Ahjussi (mister) are more appropriate. It’s usually best to wait until you are

You shouldn't call a man "Oppa" immediately upon meeting him unless it's a very casual setting. It’s usually best to wait until you are friendly or until he suggests it. "Oppa" has specific social boundaries:

A girl uses it for her biological older brother or older male cousins.

Because Korean society places high importance on age and hierarchy, "Oppa" has specific social boundaries: