A magnetized pointer (usually marked on the North end) within a compass, free to align itself with the Earth's magnetic field.(noun)
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Use "compass needle" in a sentence
"Listening to Naghma, Mariam remembered the dim glimmer of cold stars and the stringy pink clouds streaking over the Safid-koh mountains that long-ago morning when Nana had said to her, Like a compass needle that points north, a man's accusing finger always finds a woman."
"It was a state in which thought lost its direction and started to circle, like the compass needle at the magnetic pole; until finally it cut loose from its axis and travelled freely in space, like a bunch of light in the night; and until it seemed that all thoughts and all sensations, even pain and joy itself, were only the spectrum lines of the same ray of light, disintegrating in the prisma of consciousness."