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.
These new observations help fill a crucial gap in our understanding of Venus' dynamic upper atmosphere and open a new frontier in planetary monitoring from Earth orbit. Victoria Corless, Space.com, 23 July 2025 Sam Bloch connects the decisions made by people hundreds and thousands of years ago to our present planetary crisis of heat and does so in a way that’s both informative and super entertaining. Gabrielle Bellot, Literary Hub, 22 July 2025 The Planetary Health Imperative A recent commentary in The Lancet makes a compelling case for connecting planetary boundaries with planetary health, the understanding that human wellbeing depends entirely on Earth's natural systems. Cornelia C. Walther, Forbes.com, 20 July 2025 Such a propellant is already proven and is well-suited for the extreme conditions of space and meets current planetary protection requirements. New Atlas, 19 July 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 29 Jul. 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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