From Wiktionary, the free dictionary
Post + Amt.
Postamt n (strong, genitive Postamtes or Postamts, plural Postämter)
- post office, postal service
- Synonym: Post
Declension of Postamt [neuter, strong]
- “Postamt” in Duden online
- “Postamt” in Digitales Wörterbuch der deutschen Sprache