chipper
n.— «“They had ample opportunity to become addicted—on average, they’d smoked 46,000 cigarettes, but we found not the slightest evidence of dependence: they showed no signs of withdrawal when abstinent. They really could casually take smoking or leave it.” Such nonaddicted users—”chippers,” in drug culture parlance—are also seen among consumers of hard drugs.» —“Kicking Butts” by Carl Sherman Psychology Today Sept.-Oct., 1994. (source: Double-Tongued Dictionary)