Colloquial term for an unusually large, heavy cue ball made of the same phenolic resin or other modern, resilient plastic as the object balls. "Grapefruit" cue balls are frequently found on older coin-operated bar tables that do not have magnetic ball-return mechanisms. As with excessively dense, ceramic "rock" cue balls, the ball return works because the cue ball is considerably heavier than, and thereby distinguishable from, the object balls. Unlike "rocks", grapefruit balls are not prone to excessive equipment wear and tear. But because of their unusually large size, they have a very strong affect on the tangent line and thus on the accuracy of cut shots. Their weight also has a notable effect on play, as they are somewhat more difficult to draw (screw), stop and stun compared to standard and magnetic cue balls, but not to the extent of the much less resilient rock balls. Like rocks, grapefruits do generate a large amount of smash-through.