planetary

adjective

plan·​e·​tary ˈpla-nə-ˌter-ē How to pronounce planetary (audio)
1
a
: 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
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

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.
The administration announced mass firings at the National Oceanic and Atmospheric Administration (NOAA), one of the principal agencies that keep Americans apprised of the onrushing damage caused by planetary heating. Saul Elbein, The Hill, 17 Apr. 2025 Scientists have perhaps discovered the weirdest planetary system ever seen. Robert Lea, Space.com, 16 Apr. 2025 This led planetary scientist and astronomer Tristan Guillot of the Côte d'Azur Observatory, France, to propose the mushball hypothesis. Arick Wierson, MSNBC Newsweek, 16 Apr. 2025 Pinpointing the traits that boost survivorship during more stable periods and times of planetary upheaval might help scientists and conservationists protect today’s most vulnerable species. Laura Baisas, Popular Science, 16 Apr. 2025 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

Cite this Entry

“Planetary.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/planetary. Accessed 23 Apr. 2025.

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

More from Merriam-Webster on planetary

Last Updated: - Updated example sentences
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