When you're watching matt smithas the eleventh doctor of Doctor Who, and you fall off your couch and your panties fall off from seeing matt smith in screen. Most often occurs because of Moffat and the scene in "closing time" where the doctor is holding stormy and telling him not to cry.
Person 1: I was so sick last night while watching Doctor Who.
Person 2: what was wrong?
Person 1: I was suffering from Matt Smith syndrome.
Person 2: you were watching "closing time" weren't you?
Person 1: yeah...
Person 2: what was wrong?
Person 1: I was suffering from Matt Smith syndrome.
Person 2: you were watching "closing time" weren't you?
Person 1: yeah...
by MSDWfreaks April 14, 2013