Used for the leader of a sports team, a ship, or a group, similar to English 'captain'. Common in sports contexts.
彼はサッカーチームのキャプテンに選ばれた。
He was chosen as the captain of the soccer team.
キャプテンがチームをまとめる。
The captain brings the team together.
He is serving as the team's captain this year.
We discussed it and chose her as captain.
He was appointed captain by the coach.