Plain English Meaning
A ring of painted markers on the ground at non-towered airports that tells pilots flying overhead which way to fly the traffic pattern and which way the wind is blowing.
Full Definition
A system of visual indicators installed on the ground at airports without an operating control tower, providing arriving pilots with traffic pattern information. The segmented circle surrounds a wind direction indicator and typically includes traffic pattern indicators (L-shaped extensions) showing the direction of turns for each runway, along with a landing direction indicator and wind cone.
Context Anchor
Seen from the air during arrival at many airports, especially airports without an operating control tower, near the wind cone or windsock.