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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.

The in-situ package includes a magnetometer and particle detectors to sample the solar wind and interplanetary magnetic field directly.

From Science Daily • Oct. 14, 2025

You could relax on a beach, win a Super Bowl or become an interplanetary spy.

From The Wall Street Journal • Oct. 10, 2025

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

From BBC • Nov. 3, 2024

Fancies about interplanetary travel may have their sedulous followers, but skepticism about Musk’s Martian fantasy have been mounting.

From Los Angeles Times • Oct. 16, 2024

As an expert in interplanetary travel, I can tell you there are no scientific inaccuracies in the story.

From "The Martian" by Andy Weir

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.