A large, usually abrupt rise in electric current in the presence of a small increase in voltage; can occur in a confined gas between two electrodes, a gas tube, the atmosphere (as lightning), an electrical insulator, and a reverse-biased semiconductor diode. Also known as electrical breakdown.

The initial process of rolling and drawing, or a series of such processes, which reduce a casting or extruded shape before its final reduction to desired size.

The amount of pressure required at the wellhead to rupture a formation during fracture treatment.