The act of supplying another individual with important information at a crucial time. The information supplied must be of some significance within the context with which it was dropped.
Mark: "I am going to Boston, but I am not sure what I am doing"
John: "Hmm, please allow me, I love "dropping knowledge" on the likes of you. There is a Red Sox game at 7:05 pm, they're playing the Rangers, you can find tickets at stubhub.com, there is a great restaurant around the corner, here is the number to make a reservation. You should avoid taking 93 during rush hour."
Mark: "Wow, you just dropped some serious knowledge on me!"