From the only reliable news source on the net, the Onion. The Urban Dictionary here has a list of the various meanings attributed to the term pronk by Congressman Cummings. Other definitions of the term are here, here, and here. To all of this pronk nonsense, I can only quote Abraham Lincoln: “You can pronk all the people some of the time, and some of the people all the time, but you cannot pronk all the people all the time.”