Blunder

A blunder refers to a "stupid, careless mistake". Specific instances include:
 * Blunder (chess), a very poor move in chess
 * Hopetoun Blunder, an event in Australian history
 * Brand blunder, in marketing
 * Draft blunder, in American sports
 * Himalayan Blunder, in Indian history

Television

 * Blunder (TV series), a British comedy programme first shown on E4 in 2006