A high-ranking official who heads a government department or agency; a director or chief (e.g., a ministry director).
長官は会見で今後の方針を説明した。
The director (chief) explained the future policy at the press conference.
新しく就任した長官は組織改革を進めると言った。
The newly appointed chief said he would push forward organizational reforms.
災害対策本部の長官が現地に入った。
The head of the disaster response headquarters went to the site.