1. “Crucible” is a heat-resistant container (our box) in which materials (clients) can be heated (people sweat) to very high temperatures (high intensity). 2. “Crucible” means a severe test. We at the Crucible CrossFit’s each of workout is severe test of our ability as athlete. 3. A place (our box) or situation which concentrated forces interact (our workouts) to cause or influence change (in your body) or development (of ultimate athlete).