plan·e·tary | \ ˈpla-nə-ˌter-ē \

Definition of planetary 

1a : of, relating to, being, or resembling a planet

b : erratic, wandering

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

Over countless cosmic explosions and rebirths, these materials found their way into asteroids and other planetary bodies, which slammed into one another as the cosmic pot stirred. Jonathan Schifman, Popular Mechanics, "The Entire History of Steel," 9 July 2018 Instead, the researchers suggested the diamonds were produced inside an unknown planetary body. Jason Daley, Smithsonian, "Diamonds Trapped in Strange Meteorite Came From Solar System’s Earliest Planets," 19 Apr. 2018 Conversations with scientists in other disciplines can prompt creative ideas to resolve planetary puzzles, Dr. Fenton says. Eva Botkin-kowacki, The Christian Science Monitor, "Pluto dune mystery challenges scientists' frame of reference," 1 June 2018 Chris McKay, a planetary scientist at NASA's Ames Research Center involved in the research, told USA TODAY perchlorate is also a component in solid rocket fuel. Ashley May, USA TODAY, "NASA may have burned best proof of life on Mars by accident over 40 years ago," 12 July 2018 This finding matches other observations of the asteroid belt, said David Nesvorny, a planetary scientist at SWRI who was not involved with Dermott's study. Sarah Kaplan,, "Many asteroids might be remnants of 5 destroyed worlds, scientists say," 3 July 2018 Mercury retrograde — an infamous planetary transit that happens three or four times a year — gets the most attention, but all the planets experience periods of retrograde motion. Claire Comstock-gay, The Cut, "How Much Will Mars Retrograde Ruin My Life?," 26 June 2018 Frank Postberg, a planetary scientist at the University of Heidelberg in Germany and the study’s lead author, told NBC News MACH in an email. Denise Chow /, NBC News, "Saturn's moon Enceladus is now the likeliest place to find alien life," 30 June 2018 Major League Baseball’s All-Star Game will be played in Washington on July 17, and the cosmos presents a formidable planetary lineup to celebrate. Blaine P. Friedlander Jr., Washington Post, "Skywatch: July is the month of Mars," 30 June 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

15 Aug 2018

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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

: of or relating to planets


plan·e·tary | \ ˈpla-nə-ˌter-ē \

Kids Definition of planetary

1 : of or relating to a planet

2 : having a motion like that of a planet

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