magnetic field

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A condition found in the region around a magnet or an electric current, characterized by the existence of a detectable magnetic force at every point in the region and by the existence of magnetic poles.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Physics) The space around a magnet through which it exerts magnetic force; a field of force surrounding a permanent magnet, electrical current, or a moving charged particle; called also magnetic flux and field of magnetic force.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun physics a condition in the space around a magnet or electric current in which there is a detectable magnetic force and two magnetic poles are present

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun the lines of force surrounding a permanent magnet or a moving charged particle