stones

refers to the degree to which someone will stand up for them self or what one is responsible for, or, the degree to which one will go to get the job done. At work, having stones can be career-limiting if the company you work for values yes men instead of people that can actually get something done right. On film or TV, action heroes typically have major stones. However, you can have stones but no brains, which can lead to disastrous consequences if your timing sucks.