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magnetic storm

noun
  1. a temporary disturbance of the earth's magnetic field, induced by radiation and streams of charged particles from the sun.

Origin of magnetic storm

First recorded in 1855–60
Also called geomagnetic storm, solar storm.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for solar-storm

magnetic storm

noun
  1. a sudden severe disturbance of the earth's magnetic field, caused by emission of charged particles from the sun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
solar-storm in Science

magnetic storm

  1. A disturbance or fluctuation in the Earth's outer magnetosphere, usually caused by streams of charged particles (plasma) given off by solar flares. The entry of large amounts of plasma into the upper atmosphere results in intense auroral displays and other magnetic phenomena in the polar regions of the Earth. See also aurora.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
solar-storm in Culture

magnetic storm

The effect on the ionosphere of large bursts of charged particles (see electrical charge) from the sun.

Note

During a magnetic storm, radio reception can become very difficult.
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.