This is the 11650th most frequent Korean word.
남경주
"남경주" does not have a standard definition in Korean and appears to be a proper noun, possibly a name.
In this sentence, '남경주' is used as a proper noun, referring to a specific person.
남경주는 춤과 노래를 잘하는 배우입니다.
Nam Kyung-joo is an actor who is good at dancing and singing.
Here, '남경주' is used as the possessive form (with the '의' particle) to describe something associated with the person.
어제 나는 남경주의 공연을 관람했습니다.
Yesterday, I watched Nam Kyung-joo's performance.
In this case, '남경주' is referenced as an example of a type of person with specific qualities.