extragalactic

adjective

ex·​tra·​ga·​lac·​tic ˌek-strə-gə-ˈlak-tik How to pronounce extragalactic (audio)
: originating or existing outside the Milky Way galaxy
also : of or relating to extragalactic space
extragalactic astronomy

Examples of extragalactic 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.
In the slant, Shao sees evidence for an extraterrestrial, even extragalactic origin for lightning — a cosmic-ray shower. — Quanta Magazine, 6 May 2026 That’s no supernova The most common extragalactic transient luminous events, meaning flashes of light that evolve and vanish rapidly, are supernovae. — Elizabeth Rayne, Ars Technica, 27 Nov. 2023 Further confirmation of its extragalactic origin came from images taken by the Hubble Space Telescope. — Ashley Strickland, CNN Money, 22 Sep. 2025 Beginning in February 2024, the team began a six-year project called the Euclid Wide Survey, with the aim of mapping a swath of extragalactic space. — Adam Kovac, Scientific American, 7 July 2026 See All Example Sentences for extragalactic

Word History

Etymology

International Scientific Vocabulary

First Known Use

1851, in the meaning defined above

Time Traveler
The first known use of extragalactic was in 1851

Rhymes for extragalactic

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Browse Nearby Words

extraforaneous
extragalactic
extragalactic nebula
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Cite this Entry

“Extragalactic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/extragalactic. Accessed 9 Jul. 2026.

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