"charge or supply with magnetic properties," 1799, from magnet + -ize. Related: Magnetized; magnetizing. From 1785 in now-obsolete sense of "to mesmerize, hypnotize."

also magnetisation, "action of magnetizing; condition of being magnetized," 1801, noun of action from magnetize.

"deprive of magnetic polarity," 1835; see de- + magnetize. Related: Demagnetized; demagnetizing.

"de-magnetize," originally especially of ships as a defense against magnetic mines, 1940, from de- + the name of German scientist Carl Friedrich Gauss (1777-1855), a pioneer in the study of magnetics.