eight-ball noun 6verb 1forms 4 noun6 •The billiard ball, almost always black, bearing the number eight. •A pocket billiards (pool) game played with sixteen balls (a cue ball and fifteen object balls) on a pool table with six pockets. •(slang) A portion of cocaine or methamphetamine weighing ¹⁄₈ of an ounce, or 3.5 grams. •(slang, offensive) A black person. •(slang) A spherical attitude indicator.The angle-of-attack error indicator, located to the right of the attitude "eight-ball," requires some explanation. — 1960 •A kind of spherical microphone. verb1 •To outplay (an opponent) by potting all one's color balls and then the black (or eight-ball) without the opponent potting a single one. formseight-balled · eight-balling · eight-balls · eight balls