Definitions: (1) sudden and passionate excitement; (2) arousing to intense activity; (3) startling or surprising <especially by doing something very inspiring or deeply interesting>; thrilling

• Thunder is good. Thunder is impressive. But it is lightning that does the work. — Mark Twain [born Samuel Langhorne Clemens (1835-1910) American humorist
• As in nature, all is ebb and tide, all is wave motion, so it seems that in all branches of industry, alternating currents – electric wave motion – will have the sway. — Nikola Tesla (1856–1943) Serbian-American inventor, futurist, electrical & mechanical engineer

Symbol: a lightning bolt.
     Note: Lightning flashes can travel upward at 87,000 miles per second and can heat the air around it to 54,000°F (nine times the temperature of the surface of the sun).