sender
🇺🇸
/ˈsendər/
🇬🇧
/ˈsendə(r)/
A person who dispatches or transmits something, like a letter or message.
The package was returned because it had the wrong address, so the mailman gave it back to the sender.
荷物は誤った住所で返送され、郵便屋はそれを送り主に戻しました。