planetary

adjective

plan·​e·​tary ˈpla-nə-ˌter-ē How to pronounce planetary (audio)
Synonyms of planetarynext
1
a
: of, relating to, being, or resembling a planet
b
: erratic, wandering
c
: having a motion like that of a planet
planetary electrons
d
: immense
the scope of this project has reached planetary proportions
2
a
: 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

Synonyms of planetary

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Examples of planetary in a Sentence

a positively planetary new shopping development
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
There, planetary scientists Carl Agee and Karen Ziegler measured its oxygen isotopes. — Jacek Krywko, ArsTechnica, 30 Oct. 2026 Several speakers at the event stressed that a revelation that Earth has been visited by intelligent extraterrestrials would raise immediate questions about planetary defense. — Adam Kovac, Scientific American, 29 Oct. 2026 On the big-picture scale, scientists have used the planetary boundaries framework to capture the complexity of the Earth’s systems, and the impact of climate change on all of them. — Bella Webb, Vogue, 29 Oct. 2026 France has its share of problems at the moment, from civil unrest over a widening gap in living standards to the broader planetary threat of climate change. — Devorah Lauter, ARTnews.com, 29 Oct. 2026 See All Example Sentences for planetary

Word History

First Known Use

1607, in the meaning defined at sense 1a

Time Traveler
The first known use of planetary was in 1607

Phrases Containing planetary

Rhymes for planetary

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Browse Nearby Words

planetarium
planetary
planetary configuration
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Cite this Entry

“Planetary.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/planetary. Accessed 1 Nov. 2026.

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Kids Definition

planetary

adjective
plan·​e·​tary ˈplan-ə-ˌter-ē How to pronounce planetary (audio)
1
a
: of or relating to a planet
b
: having a motion like that of a planet
planetary electrons of the atomic nucleus
2
: worldwide, global
a matter of planetary concern
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