The story
Blend of Manhattan + Stonehenge. Coined by astrophysicist Neil deGrasse Tyson in 2002, in reference to the ancient English monument built in accordance with the sun's path.
Etymology from Wiktionary, CC BY-SA 4.0.
Manhattanhenge
Today it means: The twice-yearly alignment of the setting sun with the east–west streets of the main street grid in the borough of Manhattan in New York City. Full definition →