Jean Graczyk (26 May 1933 – 27 June 2004) was a professional road bicycle racer who won two points classifications in the Tour de France and has won several stages each at the Tour de France and Vuelta a España.
Before turning professional, Graczyk won an Olympic silver medal in the team pursuit for France.His nickname in the sport was Popof.
The American-French journalist René de Latour jokingly said in the British monthly Sporting Cyclist that it was because of his habit of attacking alone, or "popping off".
De Latour, however, depended too heavily on his readers' understanding of French slang, because Popof is a semi-derogatory term in French for someone of Polish background.
The "popping off" suggestion, however, is still widely believed and appears from time to time in histories of the sport.