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geomagnetism

[jee-oh-mag-ni-tiz-uh m]
noun
  1. the earth's magnetic field and associated phenomena.
  2. the branch of geophysics that studies such phenomena.

Origin of geomagnetism

First recorded in 1935–40; geo- + magnetism
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for geomagnetism

geomagnetism

noun
  1. the magnetic field of the earth
  2. the branch of physics concerned with this
Derived Formsgeomagnetic (ˌdʒiːəʊmæɡˈnɛtɪk), adjective
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
geomagnetism in Science

geomagnetism

[jē′ō-măg′nĭ-tĭz′əm]
  1. The magnetic properties of the Earth and its atmosphere.
  2. The study of these properties.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.