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interplanetary

American  
[in-ter-plan-i-ter-ee] / ˌɪn tərˈplæn ɪˌtɛr i /

adjective

  1. being or occurring between the planets or between a planet and the sun.

interplanetary British  
/ ˌɪntəˈplænɪtərɪ, -trɪ /

adjective

  1. of, relating to, or existing between planets

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of interplanetary

First recorded in 1685–95; inter- + planetary

Vocabulary lists containing interplanetary

Lesson 2

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Meanwhile, an interplanetary space race between the U.S.,

From The Wall Street Journal • Mar. 30, 2026

Decades later and after several successful interplanetary missions, Isro’s budget remains modest.

From BBC • Nov. 3, 2024

Human interplanetary exploration will be more dangerous and more costly, especially if robots can do the work, and the lack of a discernible economic return a greater obstacle.

From Los Angeles Times • Oct. 16, 2024

“It’s an unexpected interplanetary fireworks show,” said Meg Schwamb, a planetary astronomer at Queen’s University Belfast.

From New York Times • May 19, 2024

“Buddy Gui is a total meathead. I’m an artist. I’m going to have my work entered in an interplanetary contest.”

From "Landscape with Invisible Hand" by M.T. Anderson

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.