A planet which exists outside Earth's solar system.(noun)
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Use "exoplanet" in a sentence
"Smallest exoplanet is shown to be a solid, rocky world."
"Until Wednesday, the highest value Laughlin assigned to an exoplanet, which is what astronomers call a planet outside our solar system, was a measly $158."
"Meanwhile, Hubble confirms methane on the atmosphere of an exoplanet, which is getting sexed up by the media as potential extraterrestrial life."