The phrase "big risk" refers to a situation or decision that involves significant potential for loss, harm, or failure. It is often used to describe an action or venture that carries a high degree of uncertainty and has the possibility of causing severe consequences if it does not turn out as planned. The term can also be applied to individuals who are willing to take chances and accept the risks involved in pursuing their goals, even if those risks may seem daunting or dangerous. Ultimately, a "big risk" is something that requires courage, confidence, and a willingness to face potential adversity in order to achieve a greater reward or outcome.