Slam dunk

A slam dunk, also dunk or dunk shot, is a type of basketball shot that is performed when a player jumps in the air, controls the ball(s) above the horizontal plane of the rim, and scores by putting the ball directly through the basket with one or both hands. This is considered a normal field goal attempt; if successful it is worth two points. Such a shot was known as a "dunk shot" until the term "slam dunk" was coined by former Los Angeles Lakers announcer Chick Hearn.

The slam dunk is the most efficient basketball shot. Moreover, it is a crowd-pleaser. Thus, the maneuver is often extracted from the basketball game and showcased in slam dunk contests. Perhaps the most popular is the NBA Slam Dunk Contest held during the annual NBA All-Star Weekend. The first incarnation of the NBA Slam Dunk Contest was held during the half-time of the 1976 American Basketball Association All-Star Game.

Dunking was banned in the NCAA from 1967 to 1976. Many people have attributed this to the dominance of the then-college phenomenon Lew Alcindor (now known as Kareem Abdul-Jabbar); the no-dunking rule is sometimes referred to as the "Lew Alcindor rule."

The phrase "slam dunk" has since entered popular usage in American English, meaning a "sure thing": an action with a guaranteed outcome, or a similarly impressive achievement, in the same way that the baseball-inspired phrases "step up to the plate" or "he hit it out of the park" were more commonly used in previous years.

During the 1940s and '50s, 7-foot center and Olympic Gold Medalist Bob Kurland was dunking regularly during games. Yet defenders viewed the execution of a slam dunk as a personal affront that deserved retribution; thus defenders often intimidated offensive players and thwarted the move. Satch Sanders, a career Boston Celtic from 1960 to 1973, said:

"...in the old days, [defenders] would run under you when you were in the air... ...trying to take people out of games so they couldn't play. It was an unwritten rule..."

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