fictional substance in the "Superman" series, where it weakens the otherwise invulnerable hero, 1943; perhaps from elements of krypton (which is a gas) + meteorite.

Online Etymology Dictionary, © 2010 Douglas Harper

Examples from the Web for kryptonite

Contemporary Examples of kryptonite

Historical Examples of kryptonite

  • If you buy a Kryptonite bike lock and it can be defeated with a Bic pen, you're not getting very good security for your money.

    Little Brother

    Cory Doctorow