planetary nebula

noun

: a usually compact luminous ring-shaped nebula that is composed of matter which has been ejected from a hot star at its center

Examples of planetary nebula 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.
Despite their name, planetary nebulas are not related to planets. Carlyn Kranking, Smithsonian Magazine, 23 July 2024 Another class of object that the dusty blobs could hypothetically be—but are not—is a compact planetary nebula or CPN. Elizabeth Rayne, Ars Technica, 4 July 2024 As a red giant, Arcturus is at the end of its life and will eventually transform into a planetary nebula. Elizabeth Gamillo, Discover Magazine, 5 Mar. 2024 Her relative obscurity is a reminder that this planetary nebula, located about 2,300 light-years away from Earth, will outlive us all, as well as any remnant memories of us. Eric Berger, Ars Technica, 12 Dec. 2023 See all Example Sentences for planetary nebula 

Word History

First Known Use

1785, in the meaning defined above

Time Traveler
The first known use of planetary nebula was in 1785

Dictionary Entries Near planetary nebula

Cite this Entry

“Planetary nebula.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/planetary%20nebula. Accessed 15 Dec. 2024.

More from Merriam-Webster on planetary nebula

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!