What is the meaning of a flashing green light on the airfield?

A flashing green light on the airfield is universally recognized as the signal indicating that an aircraft is cleared to taxi. This signal is crucial for maintaining safe ground operations at an airfield, guiding pilots as they navigate the aircraft on the taxiways and to the runway. Understanding this signal helps ensure that aircraft can move safely around the airfield without confusion or risk of collision with other vehicles or aircraft.

In contrast, other options represent different aspects of airfield operations. An emergency signal or a clearance for takeoff would typically be communicated via solid or different colored lights, while the instruction to clear the runway would involve a specific signal to indicate that no aircraft should occupy the runway. Thus, the flashing green light is specifically associated with taxiing, reinforcing the need for pilots to be aware of their surroundings as they maneuver on the ground.