An artificial space satellite used for reconnaissance or intelligence gathering.(noun)
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Use "spy satellite" in a sentence
"At work in his “secure vault” at Hickam Air Force Base in Hawaii, Captain Hank Brandli, an air force officer charged with tracking weather systems for the top-secret National Reconnaissance Office’s ultra-classified Corona spy satellite program, had detected the early formation of a deadly “Screaming Eagle” thunderstorm with tops at 50,000 feet forming over exactly where he knew the Apollo 11 astronauts were supposed to come down."