postmaster
n.the person in charge of a local post office. They manage the staff and make sure the mail is handled correctly.
n.the official in charge of a specific post office or a postal district. While historically common, the title is now often replaced by more modern administrative designations in many postal services.
“The postmaster signed for the delivery of the new stamps.”
“After twenty years of service, the local postmaster retired and was celebrated by the entire village.”
“The postmaster general oversees the entire national network, but individual postmasters maintain responsibility for the operational efficiency and security of their respective local branches.”
The feminine form 'postmistress' is still occasionally used, though 'postmaster' is increasingly treated as a gender-neutral professional title.
From post + master.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.