Antonyms for Magnetic (opposite meaning)
WordNet sense 1 (not capable of being magnetized):
nonmagnetic
WordNet sense 2 (determined by geography):
geographic
WordNet sense 3 (impervious to the effects of a magnetic field; resistant to magnetization):
antimagnetic
WordNet sense 4 (possessing the ability to repel):
repulsive
From the ODE community, based on WordNet
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