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.
Transits also require a precise alignment between the orbital plane of a planetary system and our line of sight. Keith Cooper, Space.com, 6 June 2025 After Mercury’s debut in Cancer, and your seventh house of agreements, compromise and significant others, the messenger planet will square your planetary ruler, Saturn, on June 9, triggering tension with family or around your own repressed emotions. Valerie Mesa, People.com, 4 June 2025 Though the majority of planetary systems scatter their planets without trapping them, the portion of systems with wide-orbit planets isn’t insignificant. Sam Walters, Discover Magazine, 28 May 2025 For instance, sulfur dioxide is abundant in our own Venus’s atmosphere compared to Earth but the authors note is expected to be scrubbed from habitable planetary atmospheres by precipitation. Bruce Dorminey, Forbes.com, 20 May 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 10 Jun. 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

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