Definition
A system of blue lights placed along the edges of taxiways to mark their lateral limits and define the usable taxi surface during periods of darkness or restricted visibility.
Plain English
Blue lights running along both sides of a taxiway so pilots can see where the taxiway ends at night or in poor visibility.
Context Anchor
Seen while taxiing at night, in poor visibility, or when studying airport lighting in the Airplane Flying Handbook.
Derivation
Taxiway comes from 'taxi,' which in aviation describes an aircraft moving on the ground under its own power — borrowed from the slang 'taxi' for a hired car moving slowly through streets. 'Edge lighting' simply names what it is: lights marking the edges.
Why Pilots Care
Provides reliable visual reference to stay on the taxiway, reducing the risk of excursions onto grass or unintended runway entry.
Intuition Check
Do not confuse taxiway edge lights with runway lights. Taxiway edge lighting marks the sides of a taxiway, not the runway, and it does not give permission to enter or cross anything.
Example Sentence 1
After landing, the pilot followed the blue taxiway edge lighting system to the parking ramp.
Example Sentence 2
During a night arrival, the crew confirmed they were on the correct taxi route by tracking the blue lights of the taxiway edge lighting system.