dontopedalogy
n.— «Such a bleak and solitary youth may explain some of the brusqueness which has led to so many years of cherished Prince Philip clangers. He even coined a phrase for his special ability to say the wrong thing: dontopedalogy—the art of opening your mouth and putting your foot in it.» —“The other Royal birthday” by Gillian Glover Scotsman (Glasgow, Scotland) June 9, 2006. (source: Double-Tongued Dictionary)