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planetology

noun plan·et·ol·o·gy \ ˌpla-nə-ˈtä-lə-jē \
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Definition of planetology

plural planetologies
: a branch of astronomy that deals with the condensed matter of the solar system and especially with the planets and their moons
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planetological

play \ˌpla-nə-tə-ˈlä-ji-kəl\ adjective
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planetologist

play \ˌpla-nə-ˈtä-lə-jist\ noun

First Known Use of planetology

1865

in the meaning defined above

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