magnetic compass

from WordNet (r) 3.0 (2006)

magnetic compass
    n 1: compass based on an indicator (as a magnetic needle) that
         points to the magnetic north

from The Collaborative International Dictionary of English v.0.48

magnetic compass \magnetic compass\ n.
   An device using a magnet (such as a magnetic needle) to
   indicate the direction of magnetic north.
   [WordNet 1.5]

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