1. An important part of a Facebook profile, where friends can leave public messages for one another.
2. A terrible haircut, which is long and sticks up straight in the front, but is short everywhere else. Also known as a reverse mullet.
Jim: "Did you see that message I left on your wall?"
Ryan: "No, not yet."
Jim: "Well, it basically said that you have man boobs."
Jim: "That wasn't a compliment."