stones
1. slang Testicles. I kicked the mugger in the stones and grabbed my wallet back off him.
2. slang By extension, confidence, courage, bravado, etc. It was a real kick in the stones getting turned down for the third time. You've got some stones coming in here and asking for a raise, I'll give you that. You've got some real stones if you think you can take on someone as wealthy and powerful as him!