planetary
Americanadjective
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of or relating to a planet
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mundane; terrestrial
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wandering or erratic
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astrology under the influence of one of the planets
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(of a gear, esp an epicyclic gear) having an axis that rotates around that of another gear
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(of an electron) having an orbit around the nucleus of an atom
noun
Other Word Forms
Etymology
Origin of planetary
From the Latin word planētārius, dating back to 1585–95. See planet, -ary
Explanation
The adjective planetary has to do with any astronomical body that revolves around a star — including the earth. Rather than a circle, planetary motion takes us in an elliptical shape around the sun. In science, planetary usually describes the attributes or motion of planets. It's also used for anything that behaves in a similar way, like planetary electrons, which revolve around their atomic nucleus as if they were tiny planets. You can also talk about things that affect our entire planet using this word: "She worries a lot about the planetary effects of climate change."
Vocabulary lists containing planetary
myPerspectives 7.2
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-ary
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Combining Euronext and Deutsche Boerse would create “a pan-European market infrastructure which has a planetary scale,” Boujnah said.
From The Wall Street Journal ● Sep. 14, 2026
It will be followed by the impressive Orionid meteor shower in late October, and a planetary parade, the Leonid meteor shower and a supermoon in November.
From BBC ● Sep. 12, 2026
Understanding that relationship could reveal new clues about Earth's climate, the evolution of life, and the conditions that might make other planetary systems habitable.
From Science Daily ● Sep. 2, 2026
"Scientists usually assume that the interiors of planetary bodies are generally spherically symmetric, but this is not necessarily true," Berne says.
From Science Daily ● Aug. 30, 2026
The bigger asteroidal pieces, along with the comets, are mainly responsible for the recent craters on planetary surfaces.
From "Cosmos" by Carl Sagan
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
