Remi-what?

It's been a while since I truly didn't understand what someone was asking of me in Spanish. I was just at the post office mailing my brother's birthday card when they said, "Lo que sí te voy a pedir es que pongas el remitente." This is what I heard: "I just need to ask you to put the remitente on it." Hmm. Remitente, remitente. Normally new vocabulary words are obvious because of the context. It just wasn't sinking in. I had a blonde moment. Finally, another employee said, "your name and address." AH!!!! Of course. I forgot to put the return address. How silly. I mean what else could he have possibly been asking me to put on the envelope??