Used to refer to something that is your ultimate weakness, that which renders you powerless...in reference to Superman...whose only weakness is kryptonite.
by happythoughts October 14, 2014
Get the my kryptonitemug. It's a way of saying that something specific is your weakness. I.E. Stating that you can't help but love it, or that it's your biggest addiction.
by Grimm Whiskey October 19, 2015
Get the are my kryptonitemug.