The commander or leader of a unit; the person in charge of a squad or small group (used in military, rescue teams, clubs, etc.).
隊長は作戦開始の合図を出した。
The commander gave the signal to start the operation.
新しい隊長が部を引き継いだ。
A new leader took over the unit.
山岳救助隊の隊長は経験豊富で冷静だった。
The mountain rescue team leader was experienced and calm.