a slender magnetized steel rod that, when adjusted to swing in a horizontal plane, as in a compass, indicates the direction of the earth's magnetic fields or the approximate position of north and south.
Origin of magnetic needle
First recorded in 1840–50
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Examples from the Web for magnetic needle
Historical Examples of magnetic needle
Theory of the diurnal variation of the magnetic-needle, illustrated by experiments.
FLY, or Compass-card, placed on the magnetic-needle and supported by a pin, whereon it turns freely.The Sailor's Word-Book
William Henry Smyth
a slender magnetized rod used in certain instruments, such as the magnetic compass, for indicating the direction of a magnetic field
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