This is the 8882nd most frequent Korean word.
강석구
"강석구" is typically a Korean name and does not have a specific meaning as a standalone word.
The word '강석구' is used here as a proper noun representing the name of a person.
강석구는 오늘 회사에서 발표를 했어요.
Kang Seok-gu gave a presentation at work today.
The word '강석구' again serves as a proper noun, referring specifically to the user's friend.
내 친구 강석구는 축구를 잘해요.
My friend Kang Seok-gu is good at soccer.
Here, '강석구' is used as a name being commented on for its rarity. It is treated as a subject of discussion.