magnetic needle
Noun: A magnetic needle is a slender, magnetized bar, typically made of steel, that is balanced on a nearly frictionless pivot. It is the essential component of a magnetic compass, designed to align itself with the Earth's magnetic field, thereby indicating the direction of the Earth's magnetic poles (roughly north and south).
The term magnetic needle specifically refers to the moving, magnetized part inside a compass. It is used when discussing the principle, construction, or operation of traditional directional compasses. - The hiker checked the magnetic needle to ensure he was heading north. - The invention of the magnetic needle was crucial for ancient navigation. - A slight tremor disturbed the delicate balance of the magnetic needle.
- Scientific Principle: The magnetic needle aligns itself along the horizontal component of the Earth's magnetic field lines. Its north-seeking pole points towards the Earth's magnetic north pole.
- Historical Context: The magnetic needle was a pivotal technological advancement, first used for navigation in China before spreading to the Islamic world and Europe.
- Compass needle: A more common, general term for the magnetic needle in a compass. While often synonymous, "compass needle" can sometimes refer to the entire indicator, including the card or dial.
- Magnetic compass: The complete instrument that houses the magnetic needle.
- Lodestone: A naturally magnetized piece of the mineral magnetite, historically used to magnetize early magnetic needles.
- Compass needle (near synonym)
- Directional needle
The magnetic needle has one primary meaning: the physical, magnetized indicator in a compass. It is a concrete noun referring to a specific object. It is not used idiomatically or as part of common phrasal verbs.
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a slender magnet suspended in a magnetic compass on a mounting with little friction; used to indicate the direction of the earth's magnetic pole
