verb (v)

• erase (a magnetic storage device)(verb.communication)

  Synonym:
  demagnetise
  

  source: wordnet30
• make nonmagnetic; take away the magnetic properties (of)(verb.change)

  Example:
  Demagnetize the iron shavings.
  

  Synonym:
  degauss, demagnetise
  Antonym:
  magnetise, magnetize
  

  source: wordnet30
• To deprive of magnetic properties. See Magnetize.(verb)

  source: webster1913