The story
Etymology from Wiktionary, CC BY-SA 4.0.
Today it means: An optical phenomenon that occurs when sunlight reflects off the surface of water (an ocean, lake or river) directly towards a satellite sensor viewing the surface, so that in the sunglint area of a satellite image, smooth water appears as a silvery mirror, while rougher surface water is relatively dark. Full definition →
Etymology from Wiktionary, CC BY-SA 4.0.