Innefective medication given to someone to psychologically make them well. They think that they have been given medication that makes them better so their mind makes themself get better because they think the drug is taking effect. Confusing.
Dr. Jimbob: We got a guy at the front desk complaining that he is critically ill. I don't think he is though, I mean I've checked him over and he's fine.
Dr. Thomas: Just give him a placebo, that should sort it.
A phrase to describe getting the short end of the stick, or being left holding the bag! From the literal: group of guys having a circle jerk "on" a cookie placed in the middle of the group. The last one to climax has to "eat the cookie".
John was the one left to eat the cookie when all his friends found chicks to hook up with at the bar.