Korean Slangs commonly used among young guys

쩔다 (zzul dah)
it means "killingly cool", F***ing awsome
ex. 이야, 춤 쩐다.
iyah, choom zzun dah (gosh, he/she dances F***ing awsome

Jaang nan anindae
it means "killingly cool"
ex. 저 아가씨, 장난아닌데...

Jeo, agahssi, jaang nan anindae (gosh that lady is freaking hot!)