de·​perm | \ (ˈ)dē¦pərm \

Definition of deperm

: to demagnetize partly (a ship's steel hull) as a precaution against magnetic mines by surrounding in dry dock with a large coil through which is sent an alternating current very strong at first but gradually diminishing in intensity — compare degauss

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History and Etymology for deperm

de- + permanent magnetism

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Cite this Entry

“Deperm.” Dictionary, Merriam-Webster, Accessed 3 Jul. 2020.

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