What does AGL stand for in aviation terminology?

AGL stands for "Above Ground Level" in aviation terminology. This term is used to describe altitude or height measurements in relation to the ground surface directly below an aircraft. For example, when reporting altitude, saying an aircraft is flying at 500 feet AGL means that the aircraft is 500 feet above the ground at that specific location, which can be critical for avoiding obstacles like buildings or trees. Understanding AGL is essential for safe flight operations, particularly in low-altitude environments where terrain and obstacles can significantly influence flight safety. This concept is distinct from altitude measurements based on sea level (MSL) and is commonly used in air traffic control and navigation.