post office
Advanced English dictionary
+ noun1 [C] a place where you can buy stamps, send letters, etc: Where's the main post office? + You can buy your stamps at the post office. + a post office counter
2 (the Post Office) [sing.] (abbreviation PO) the national organization in many countries that is responsible for collecting and delivering letters, etc: He works for the Post Office.
3 [U] (AmE) = POSTMAN'S KNOCK
Concise dictionary
noun+a local branch of the United States Post Office
+an independent agency of the federal government responsible for mail delivery (and sometimes telecommunications) between individuals and businesses in the United States
+a children's game in which kisses are exchanged for pretended letters
