Drag is the resistance an object experiences as it moves through air or another fluid. In physics, more speed, larger surface area, and less streamlined shape usually mean more drag. The term matters in cyber security because many security systems also operate inside performance limits: sensors, appliances, robots, drones, and even cooling or airflow in data centers can all be affected by resistance, latency, and energy loss.
Attackers can exploit drag indirectly by forcing a system to work harder than expected. For example, a flood of requests can create network and CPU drag, slowing services until they become unreliable. Defenders also use controlled drag on purpose: rate limiting, throttling, sandbox detonation delays, and traffic inspection all add friction to make abuse harder and detection easier. In short, drag is a reminder that security is not only about correctness, but also about how well a system keeps functioning under stress.