magnetic field

American  

noun

1. a region of space near a magnet, electric current, or moving charged particle in which a magnetic force acts on any other magnet, electric current, or moving charged particle.

2. magnetic intensity.

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magnetic field British  

noun

1. a field of force surrounding a permanent magnet or a moving charged particle, in which another permanent magnet or moving charge experiences a force Compare electric field

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magnetic field Scientific  

1. A field of force associated with changing electric fields, as when electric charges are in motion. Magnetic fields exert deflective forces on moving electric charges. Most magnets have magnetic fields as a result of the spinning motion of the electrons orbiting the atoms of which they are composed; electromagnets create such fields from electric current moving through coils. Large objects, such as the earth, other planets, and stars, also produce magnetic fields.

2. See Note at magnetism

3. See magnetic field strength

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magnetic field Cultural  

1. A magnetic field is said to exist in a region if a force can be exerted on a magnet. If a compass needle is deflected when it is put at a particular location, we say a magnetic field exists at that point, and the strength of the field is measured by the strength of the force of the compass needle. The Earth, the sun, and the Milky Way galaxy all have magnetic fields. All known magnetic fields are caused by the movement of electrical charges. Electrons in orbit in atoms give rise to magnetic fields, so that every atom is, like the Earth, surrounded by a magnetic field. (See magnet and magnetism.)

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Etymology

Origin of magnetic field

First recorded in 1835–45

Example Sentences

See Examples For:

magnetic field

The second is the "tangled magnetic field lines" in the Sun's atmosphere that constantly snap and then reconnect.

From BBC ● Aug. 14, 2026

And for those looking closely they may have seen small loops of pink gas called prominences following the Sun's turbulent magnetic field.

From BBC ● Aug. 12, 2026

The phenomenon will present scientists with a rare opportunity to study the Sun's atmosphere and its outermost layer, as they seek to uncover secrets about solar winds and our star's magnetic field.

From Barron's ● Aug. 11, 2026

During reconnection, twisted magnetic field lines snap open and reconnect in a different arrangement.

From Science Daily ● Aug. 8, 2026

When the magnetic field is working, these rays are safely herded away from the Earth’s surface and into two zones in near space called the Van Allen belts.

From "A Short History of Nearly Everything" by Bill Bryson