1. Aegyo. "Ae" meaning "love", and "Gyo" meaning "beautiful", when people "show their aegyo" it means when they act all cute & fluffy x3
2. Bias. A bias is a person who you like most in a group. Many KPoppers have something called a bias list, which is a list of their biases in all their groups.(Here's my bias list.) An ultimate bias is a person who you like most out of all your favorite groups.
3. Ayo. It's just a way to say "Hey you" or "Hello".
4. Fighting. It something people say to encourage or cheer on someone. Basically it's like saying, "Go"! People also say fighting as hwaiting because some Koreans have trouble saying the letter F. If someone says hwaiting, you know they mean fighting.
5. Oppa. It's what girls call their brother/boyfriend/dude who's older than them. (Not like, retirement-old, but like, maybe a few years older.) Some people spell oppa as oppar. Boys DO NOT call others Oppa. Instead, they say hyung, which means brother. If a boy is gay, however, they can call their boyfriend oppa.
6. Unni. Sometimes it's spelled unnie. It's what girls call their sister/girls who are older than them. Boys use the term Noona for that.
7. Maknae. People will call someone who's the youngest (in a group or anywhere else) a maknae.
8. Omo. When someone says "Omo!!", they mean "Oh my gosh!!"
9. Daebak. Daebak is said when, maybe, someone is shocked/surprised. It's a little like saying Omo but it kinda means something different.
10. Bbuing bbuing. This is what people say/do when they show their aegyo. Saying "bbuing bbuing~" is different from doing bbuing bbuing.
Haha! This was fun to write. That should be it for now, until next time!