Definition
A device on or near an airport that visually shows the direction in which landings and takeoffs should be made. The most common form is the tetrahedron — a large arrow- or wedge-shaped marker that points in the direction of landing.
Plain English
A ground marker at an airport that shows pilots which way to land and take off, based on the current wind.
Context Anchor
You may see a Landing Direction Indicator at an airport when checking the airport environment from the air or while preparing to enter the landing area.
Derivation
Indicator comes from a Latin word meaning “to point out” or “to show.” That fits this use: the device points out the direction pilots should use for landing and takeoff.
Why Pilots Care
It shows the preferred runway direction so all aircraft operate in the same flow and avoid conflicts.
Intuition Check
Do not assume this simply shows where the wind is coming from. A Landing Direction Indicator shows the direction currently designated for landing and takeoff; wind may be one reason for that choice, but the device is showing the airport’s selected direction.
Example Sentence 1
On the downwind leg, the pilot glanced at the landing direction indicator to confirm Runway 27 was the active runway.
Example Sentence 2
Wind shift caused the landing direction indicator to change, so the tower announced a new active runway.