lightning

adj. of or pertaining to lightning

n. flash or streak of light in the sky caused by the discharge of an electric spark in a thundercloud

For information on lightning precautions, see Lightning safety. For other uses, see Lightning (disambiguation) Lightning is an atmospheric discharge of electricity, which typically occurs during thunderstorms, and sometimes during volcanic eruptions or dust storms. A bolt of lightning can travel at a speed of , and can reach temperatures approaching , hot enough to fuse soil or sand into glass channels. There are over 16 million lightning storms every year.
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Lightning visible discharge of electricity between storm clouds or between the clouds and an earthing point at ground level. [more]Lightning - Community and Resources

Noun
1. abrupt electric discharge from cloud to cloud or from cloud to earth accompanied by the emission of light
(hypernym) atmospheric electricity
(hyponym) forked lightning, chain lightning
2. the flash of light that accompanies an electric discharge in the atmosphere (or something resembling such a flash); can scintillate for a second or more
(hypernym) flash
(hyponym) heat lightning

(vb. n.)
Lightening.
  

(n.)
The act of making bright, or the state of being made bright; enlightenment; brightening, as of the mental powers.
  

(n.)
A discharge of atmospheric electricity, accompanied by a vivid flash of light, commonly from one cloud to another, sometimes from a cloud to the earth. The sound produced by the electricity in passing rapidly through the atmosphere constitutes thunder.