Cliff Thorburn (born 16 January 1948) is a Canadian retired professional snooker player. Nicknamed 'The Grinder' because of his slow, determined style of play, he won the World Snooker Championship in 1980, defeating Alex Higgins 18–16 in the final. He is generally recognised as the sport's first world champion from outside the United Kingdom—since Australian Horace Lindrum's 1952 title is usually disregarded—and he remains the only world champion from the Americas. He was runner-up in two other world championships, losing 21–25 to John Spencer in the 1977 final and 6–18 to Steve Davis in the 1983 final. At the 1983 tournament, Thorburn became the first player to make a maximum break in a World Championship match, achieving the feat in his second-round encounter with Terry Griffiths.