Definition: something that is sure to happen or to be successful
“The replays of Jerry West jump shot at the buzzer, a slam dunk by Wilt Chamberlin, and a twisting drive by Elgin Baylor are presented in the I,P-T by Doug Ives.”
—Adv’t, The Independent [Long Beach CA], 29 April 1969
The slam dunk is the more forceful rendition of the simple dunk, which is itself a shot whereby a basketball player jumps high and throws the ball directly into the hoop, making contact with either one or two hands on the rim. Slam dunk began to be used to describe this type of shot in the late 1960s, often initially in reference to goals scored by Wilt Chamberlain.
The word quickly proved to be flexible, and began to be used in a figurative fashion, or in reference to a forceful throwing of a ball in sports other than basketball.
“The planet was still quivering from the sight of the stately Prothro, the man in control striding onto the field to challenge the officials Sunday when Wooden let down his dignity to slam-dunk the press at Monday’s basketball writers’ luncheon.”
— The Independent [Long Beach, CA], 8 December 1971
“Today you mostly see the slam dunk in the end zone. Runners promenading into the scoring sector hurl the ball against the turf.”
— The Terra Haute Tribune [Terre Haute, IN] 15 November 1972
By the 1980s the slam dunk had become part of our general vernacular, and was being used to describe something that was assured to happen, or something that was thought to be easy. This makes a certain amount of sense, given the way that great players can make the dunk look effortless. For most of us, however, the slam dunk is anything but easy.
“I’m certainly not going to be a slam dunk for just any kind of development,” he added.
— Los Angeles Times, 13 March 1983