- a brilliant electric spark discharge in the atmosphere, occurring within a thundercloud, between clouds, or between a cloud and the ground.
- to emit a flash or flashes of lightning (often used impersonally with it as subject): If it starts to lightning, we'd better go inside.
- of, relating to, or resembling lightning, especially in regard to speed of movement: lightning flashes; lightning speed.
Origin of lightning
Examples from the Web for lightning
Should lightning strike and Hillary Clinton forgoes a presidential run, Democrats have a nominee in waiting.Sen. Warren’s Main Street Crusade to Pressure Clinton
January 8, 2015
Second, Michelle served as a lightning rod in the sense of drawing attacks away from other reform groups.A Letter of Thanks to Michelle Rhee
August 16, 2014
There were flashes of lightning outside and the rumble of thunder.The Gentle Giant Cut Down by Cops
July 24, 2014
Improvements in lightning tracking help scientists know where to send aircraft to look for fires.Fighting Wildfire With Satellites, Lasers, and Drones
July 9, 2014
Setting up the company “came to me as a lightning bolt last summer,” Lear tells me.Adventures in Gay History With Oscar Wilde
June 11, 2014
Often, during a thunderstorm a tree had been hit by lightning.Ancient Man
Hendrik Willem van Loon
Andrew went on with his lightning summary of the things he passed.Way of the Lawless
The action is as quick as thought, and thought is as quick as lightning.The Conquest of Fear
She looked young to be a doctor, he decided, after that lightning survey.Chip, of the Flying U
B. M. Bower
A change swift as lightning had come over me, a sudden exultation.Green Mansions
W. H. Hudson
- a flash of light in the sky, occurring during a thunderstorm and caused by a discharge of electricity, either between clouds or between a cloud and the earthRelated adjectives: fulgurous, fulminous
- (modifier) fast and suddena lightning raid
Word Origin and History for lightning
late 13c., present participle of lightnen "make bright," extended form of Old English lihting, from leht (see light (n.)). Meaning "cheap, raw whiskey" is attested from 1781, also sometimes "gin." Lightning bug is attested from 1778. Lightning rod from 1790.
- A flash of light in the sky caused by an electrical discharge between clouds or between a cloud and the Earth's surface. The flash heats the air and usually causes thunder. Lightning may appear as a jagged streak, as a bright sheet, or in rare cases, as a glowing red ball.
A Closer Look: As storm clouds develop, the temperature at the top of the cloud becomes much cooler than that at the bottom. For reasons that scientists still do not understand, this temperature difference results in the accumulation of negatively charged particles near the base and positively charged particles near the top of the storm cloud. The negatively charged particles repel the electrons of atoms in nearby objects, such as the bases of other storm clouds or tall objects on the ground. Consequently, these nearby objects take on a positive charge. The difference in charge, or voltage, builds until an electric current starts to flow between the objects along a pathway of charged atoms in the air. The current flow heats up the air to such a degree that it glows, generating lightning. Initially, a bolt of lightning carrying a negative charge darts from one storm cloud to another or from a storm cloud to the ground, leaving the bottom of the cloud with a positive charge. In response, a second bolt (reverse lightning) shoots in the opposite direction (from the other storm cloud or the ground) as the mass of negative charges on it moves back to neutralize the positive charge on the bottom of the first cloud. The heat generated by the lightning causes the air to expand, in turn creating very large sound waves, or thunder.