What is demagnetism?

Answer 1

Demagnetization is the removal of a permanent magnetic field from an object. Such as the "degaussing" of a CRT to remove color shifting, or the erasing of a magnetic medium (tape, floppy...).

Answer 2

demagnetism is when you remove the magnetism from certain magnetic objects causing magnets not to attract to metal anymore or as strong as it once did

Answer 3

Thing made of iron, or iron-like metals can become magnetic. If you don't want them to magnetic you can do things to them to make them give up their magnetism, and that's demagnetizing.