Definition of "supercritical mass" []

• A mass of fissile material that is more than sufficient to sustain a nuclear chain reaction (noun)

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• ""To crush a solid ball of plutonium into a denser, supercritical mass is theoretically conceivable," Foote told Joe, "if the ball is crushed by a perfectly symmetrical shock wave, which is possible if every one of these lenses is detonated in the same millionth of a second.""