n. A crucial or decisive point or situation; a turning point.n. An unstable condition, as in political, social, or economic affairs, involving an impending abrupt or decisive change.n. A sudden change in the course of a disease or fever, toward either improvement or deterioration.n. An emotionally stressful event or traumatic change in a person's life.n. A point in a story or drama when a conflict reaches its highest tension and must be resolved.