planetary
Americanadjective
-
of or relating to a planet
-
mundane; terrestrial
-
wandering or erratic
-
astrology under the influence of one of the planets
-
(of a gear, esp an epicyclic gear) having an axis that rotates around that of another gear
-
(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
Looking to grow your vocabulary? Check out this interactive, curated word list from our team of English language specialists at Vocabulary.com – one of over 17,000 lists we've built to help learners worldwide!
-ary
Interested in learning more words like this one? Our team at Vocabulary.com has got you covered! You can review flashcards, quiz yourself, practice spelling, and more – and it's all completely free to use!
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.
By surveying large regions of the sky, Roman is expected to give researchers a powerful new way to study the history and structure of the universe while also expanding our understanding of distant planetary systems.
From Science Daily ● Aug. 24, 2026
Turtle and Lorenz are seasoned hands in the planetary science world.
From Los Angeles Times ● Aug. 22, 2026
It’s considered in the climate community to be the likeliest proposal for offsetting about 1 degree Celsius of planetary warming that computer models attribute to accumulated emissions.
From The Wall Street Journal ● Aug. 11, 2026
It could be days or even weeks before the full picture of what happened and what we can learn from it is known - but for planetary geologists, this accidental collision is a scientific gift.
From BBC ● Aug. 5, 2026
Similarly, Ptolemy had demonstrated that no homocentric planetary system could account for the observed phenomena, but philosophers were still trying to produce such a system well into the sixteenth century.
From "The Invention of Science" by David Wootton
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.
