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

Examples of planetary in a Sentence

a positively planetary new shopping development
Recent Examples on the Web For more than two months, Sojourner traveled hundreds of miles and transmitted an unprecedented amount of data directly from the red planet back to Earth, paving the way for future planetary exploration. Meghan Willcoxon, Journal Sentinel, 1 July 2022 Earlier this year, during a House Science Committee hearing on planetary defense, lawmakers registered their displeasure with NASA's decision to delay the launch of NEO Surveyor to at least 2028 for budgetary reasons. Eric Berger, Ars Technica, 27 June 2022 The first —- which is currently the most accepted —- is that the Asteroid Psyche was originally an ordinary asteroid that had lost most of its rocky layers due to violent collisions with other small planetary bodies. Bruce Dorminey, Forbes, 25 June 2022 Mercury, Venus, Mars, Jupiter and Saturn were to line up in the pre-dawn sky, a planetary procession that could be seen above the eastern horizon every morning through the end of June, AccuWeather said. Editors, USA TODAY, 24 June 2022 The moon will represent the Earth’s relative position in the alignment, meaning this is where our planet will appear in the planetary order. Megan Marples, CNN, 23 June 2022 Britt Wray, a human and planetary health fellow at Stanford University and the London School of Hygiene and Tropical Medicine, knows exactly what that feels like. Heather Hansman, Outside Online, 18 June 2022 For a while the rare planetary set piece unfolded largely unnoticed. Tim Folger, Scientific American, 18 June 2022 The quality of the air, the angle of the sun — this art belongs to a very particular piece of planetary geography. Chris Richards, Washington Post, 16 June 2022 See More

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.

First Known Use of planetary

1607, in the meaning defined at sense 1a

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Time Traveler for planetary

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The first known use of planetary was in 1607

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Dictionary Entries Near planetary



planetary configuration

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Last Updated

4 Jul 2022

Cite this Entry

“Planetary.” Dictionary, Merriam-Webster, Accessed 7 Jul. 2022.

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More Definitions for planetary


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

More from Merriam-Webster on planetary

Nglish: Translation of planetary for Spanish Speakers

Britannica English: Translation of planetary for Arabic Speakers


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