(idiomatic) Incredibly fast.

(astronomy, meteorology) An upper-atmospheric optical phenomenon associated with thunderstorms, in which the lightning bolt projects straight into the upper atmosphere.

A round of a game or contest that gives participants a fixed time in which to achieve as much as possible.

plural of lightning round

(idiomatic) A difficult or challenging feat, particularly to attempt such a feat. / (idiomatic) Great, unlikely, fleeting success, particularly entrepreneurial or in the media.

(slang) To be executed by electric chair.

Lightning in angular, zigzag, or forked flashes.

lightning arrester

A device used on electrical and telecommunications systems to protect the insulation and conductors from the damaging effects of lightning. Typically, it has a high-voltage terminal and a ground terminal. When a surge travels along the power line to the arrester, the current from the surge is diverted through the arrester, in most cases to earth.

Lightning that occurs too far away for the resulting thunder to be audible by the observer.