plan·​e·​tary | \ ˈpla-nə-ˌter-ē How to pronounce planetary (audio) \

Definition of planetary

1a : of, relating to, being, or resembling a planet
c : having a motion like that of a planet planetary electrons
d : immense the scope of this project has reached planetary proportions
2a : of, relating to, or belonging to the earth : terrestrial
b : global, worldwide planetary politics
3 : having or consisting of an epicyclic train of gear wheels

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Examples of planetary in a Sentence

a positively planetary new shopping development
Recent Examples on the Web Mezilis also discussed his moon-selfie-sphere idea with Jim Bell, a planetary scientist at Arizona State University, who has developed camera systems for several Mars rovers, including Perseverance. Eric Adams, Wired, "The LA Musician Who Helped Design a Microphone for Mars," 17 Feb. 2021 Astronomers often use these apparent alignments to help calculate orbits more precisely, to estimate the sizes of distant worlds and to study planetary systems circling other stars. Robert Lee Hotz, WSJ, "A Christmas Star? Jupiter and Saturn Alignment Sparks Comparisons," 20 Dec. 2020 According to Michael Wong, a planetary scientist at the University of California in Berkeley, the overarching takeaway from these new images is how relatively blinkered most of our earlier views have been. Lee Billings, Scientific American, "Juno Delivers Stunning New Views of Great Red Spot," 13 July 2017 Sara Seager, a planetary expert at the Massachusetts Institute of Technology, whose story helps frame the film’s narrative, said the emergence made perfect sense. New York Times, "The Webb Telescope, NASA’s Golden Surfer, Is Almost Ready, Again," 2 Feb. 2021 The Paris Agreement is a planetary accord to stop greenhouse gas emissions—and to fight the warming climate, rising sea levels, mass extinctions, and extreme weather that come along for the ride. Rahul Rao, Popular Science, "The US is back in the Paris Agreement. What does that mean?," 22 Jan. 2021 Apple Music’s programming is chiefly organized around one superstar talent, Zane Lowe, and there simply aren’t many planetary talents like that in podcasting. Nicholas Quah, Vulture, "So, Is Apple Building a Netflix for Podcasts?," 19 Jan. 2021 It’s a promising remote method for exploring our solar system and understanding planetary history. Save this story for later. Daniel Oberhaus, Wired, "NASA Is Training an AI to Detect Fresh Craters on Mars," 19 Jan. 2021 Now government scientists have crunched the numbers behind the planetary chaos. Paul Douglas, Star Tribune, "Old Man Winter Pulls His Punch - Accumulating Snow This Weekend," 19 Jan. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'planetary.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of planetary

1607, in the meaning defined at sense 1a

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Time Traveler for planetary Time Traveler

The first known use of planetary was in 1607

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Statistics for planetary

Last Updated

6 Mar 2021

Cite this Entry

“Planetary.” Dictionary, Merriam-Webster, Accessed 8 Mar. 2021.

Style: MLA
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More Definitions for planetary



English Language Learners Definition of planetary

technical : of or relating to planets


plan·​e·​tary | \ ˈpla-nə-ˌter-ē How to pronounce planetary (audio) \

Kids Definition of planetary

1 : of or relating to a planet
2 : having a motion like that of a planet

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