This is the 68th most frequent Korean word.
세계
"세계" means "world."
Here, '세계' refers to the physical world or the Earth as a whole.
세계는 넓고 다양하다.
The world is vast and diverse.
In this sentence, '세계' is used to denote a global scale or competitive context.
그는 세계 챔피언 타이틀을 획득했다.
He achieved the World Champion title.
In this context, '세계' symbolizes the entire global human society or international community.