<jargon> Any stimulus compelling enough to yank one right out of hack mode. Classically used to describe being dragged away by an SO for immediate sex, but may also refer to more mundane interruptions such as a fire alarm going off in the near vicinity. Also called an NMI (non-maskable interrupt), especially in PC-land.
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Nearby terms: print server « Print Services Facility « priority inheritance « priority interrupt » priority inversion » priority queue » priority scheduling