a uniformed security officer holds up his hand in a firm stop gesture toward a passenger. The passenger carries a large bag that clearly contains prohibited items visible through the X-ray screen. The officer points to a prominent display of banned objects while shaking his head decisively. The passenger's face shows disappointment as he realizes his items cannot pass through. Other travelers in line watch the interaction while security personnel maintain their vigilant positions. the action of prohibiting or forbidding something from proceeding