General English

General Science

  • noun a discharge of electricity between clouds and the earth, seen as a bright flash and accompanied by the sound of thunder which is heard after a short delay


  • noun a powerful and sudden electrical discharge from a cloud


  • A luminous electrical discharge between a cloud and the ground, between clouds, or within the same cloud, due to potential differences which become strong enough to break down the insulation that the intervening air provides. A lightning discharge may consist of multiple strokes, each of which is preceded by a leader. The current in a typical discharge is about 10,000 to 20,000 amperes, with peaks which can exceed 100,000 amperes. The burst of heat which accompanies a lightning discharge forces the surrounding air to expand explosively, producing shock waves heard as thunder. Also called lightning discharge.


  • noun another name for the drug crack

Origin & History of “lightning”

Etymologically, lightning is simply something that illuminates, or ‘lightens’, the sky. The word is a contraction of an earlier lightening, a derivative of lighten ‘make light’. The Old English word for ‘lightning’ was lēget, which is related to light. In middle English it became leit, and later leiting, but in the 14th century lightning took over as the main form.