The United States Post Office is a well-known institution in the country, but did you know that there are a variety of synonyms that can be used to describe it? Some of the most common include the US Postal Service, USPS, the Postal Service, and the Post Office Department. Other variations include the American Postal Service, the US Mail, and the United States Postal System. Regardless of what term you use, the function of the organization remains the same - to deliver mail and packages to people across the country. So whether you are sending a letter to your grandma or a package to your friend across the country, you can trust the US Post Office to get it there safely and reliably.