Toughness, masculinity, confidence, fearlessness, assuredness in any and all endeavors of life and living.
Usually applied to men as having a direct relationship between their testacle size/constitution and their male prowess; but can include women.
Can also be used to diminish the masculinity of a male by referring to his lack of having stonez.
Positive - "Man, did you see how that little dude took on that guy who was over twice his size?!" "He had a pair of stonez on him!"
Negative - "Man quit acting like a little bitch and get some stonez!"