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interplanetary

adjective

in·​ter·​plan·​e·​tary ˌin-tər-ˈpla-nə-ˌter-ē How to pronounce interplanetary (audio)
: existing, carried on, or operating between planets
interplanetary dust
an interplanetary flight
interplanetary spacecraft

Examples of interplanetary in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The recent images from OSIRIS-APEX mark an early milestone, confirming that its cameras and instruments are fully operational after years in deep space, and that the spacecraft is on course for its interplanetary journey. Samantha Mathewson, Space.com, 28 Nov. 2025 From the invention of the wheel to the launch of interplanetary missions, engineering has always been the driving force behind human progress. Atharva Gosavi, Interesting Engineering, 19 Nov. 2025 But becoming an interplanetary species is an enormous challenge. Big Think, 12 Nov. 2025 The result shows that AI can be safely used in space, the researchers said, which will be critical in deep-space or interplanetary missions where direct control is impossible because signals take hours or days to reach the probe. Prashant Rao, semafor.com, 11 Nov. 2025 See All Example Sentences for interplanetary

Word History

First Known Use

1691, in the meaning defined above

Time Traveler
The first known use of interplanetary was in 1691

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Cite this Entry

“Interplanetary.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/interplanetary. Accessed 30 Nov. 2025.

Kids Definition

interplanetary

adjective
in·​ter·​plan·​e·​tary
ˌint-ər-ˈplan-ə-ˌter-ē
: between planets
interplanetary space
interplanetary travel

More from Merriam-Webster on interplanetary

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