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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.

Previous work has shown that the hardy microbe can withstand radiation and desiccation, making it a candidate for interplanetary survival.

From Science Daily • Mar. 3, 2026

Genly Ai’s mission is to persuade the governments on Gethen to join a larger interplanetary coalition.

From The Wall Street Journal • Dec. 12, 2025

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

From BBC • Nov. 3, 2024

Engineered by JPL, the $5-billion Europa Clipper spacecraft is the largest interplanetary probe ever built by the space agency.

From Los Angeles Times • Oct. 9, 2024

It had been almost two years sailing through interplanetary space.

From "Cosmos" by Carl Sagan

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.