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

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Examples of planetary in a Sentence

a positively planetary new shopping development

Recent Examples on the Web

Take a break on Sunday, when the Sun squares Neptune, your planetary ruler. Venus Australis,, "Your Horoscope This Week," 9 June 2019 Another theory holds that the gap results directly from planetary genesis, maybe because of the location or makeup of the gas and dust left over from the star’s birth. Quanta Magazine, "As Planet Discoveries Pile Up, a Gap Appears in the Pattern," 16 May 2019 Globus, like O’Neill and Bezos, also firmly believes that humanity’s destiny doesn’t lie on Earth or any other planetary surface. Matt Blitz, Popular Mechanics, "Why the World's Richest Man Wants Humans To Live on Floating Space Cities," 10 May 2019 There is a change of pace mid-May when your go-getter planetary ruler changes signs. Randon Rosenbohm, Allure, "What May’s Aries Horoscope Means for You," 30 Apr. 2019 Philip Metzger, a planetary scientist who led the study, said in a statement to UCF Today. Janay Moore, Teen Vogue, "Pluto Should Be a Planet Again According to These Scientists," 11 Sep. 2018 The study provides new insights into planetary formation in our own solar system and offers clues to the chemistry of planets circling other stars. Jeffrey Kluger, Time, "Uranus Smells Terrible. There, We Said it," 24 Apr. 2018 As the day approaches when extra-planetary travel becomes more accessible (at least, initially, to billionaire space tourists), researchers are developing tools to ease the transition to weightless living. Leigh Kamping-carder, WSJ, "How a Robotic Tail Could Help Future Space Travelers," 5 Apr. 2019 Meanwhile, the Mars Reconnaissance Orbiter will record the entry, descent, and landing of InSight in real time, but because of planetary dynamics, that spacecraft won't relay that information back to Earth for about three hours. Eric Berger, Ars Technica, "Here’s how NASA will attempt to land on the Red Planet Monday," 26 Nov. 2018

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.

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First Known Use of planetary

1607, in the meaning defined at sense 1a

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Statistics for planetary

Last Updated

20 Jun 2019

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Time Traveler for planetary

The first known use of planetary was in 1607

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English Language Learners Definition of planetary

technical : of or relating to planets


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

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