How is "aerodynamic drag" defined in aviation?

Aerodynamic drag is accurately defined as the opposing force that acts against the aircraft's forward motion. This force is generated as the aircraft moves through the air, and it works in the opposite direction to the aircraft's thrust, which is the force propelling it forward. As the aircraft's speed increases, so does the aerodynamic drag, which primarily arises from two components: skin friction drag and pressure drag.

Understanding this concept is crucial because it impacts fuel efficiency and performance. Pilots and engineers must know how to manage aerodynamic drag to optimize the aircraft's design and operation for better speed and fuel consumption.