Postmaster
Black's Law Dictionary · Henry Campbell Black, M.A. · 1910
Black's Law Dictionary
An officer of the United States, appointed to take charge of a local post-office and transact the business of receiving and forwarding the mails at that point, and such other business as is committed to him under the postal laws.
— Postmaster general. The head of the post-office department. He ls one of the president's cabinet.