supernova
noun
Did you know?
A nova, despite its name, isn't actually a "new" star, but rather one that wasn't noticed until it exploded, when it may increase in brightness by a million times before returning to its previous state a few days later. A supernova is far larger; a star in its supernova state may emit a billion times as much light as previously. After a few weeks it begins to dim, until it eventually ceases to exist; it's often replaced by a black hole. (Though remains that were shot out into space may survive; those of a great supernova seen in A.D. 1054 are now known as the Crab Nebula.) All this may serve as a warning to those human stars whose fame explodes too rapidly; supernovas of this kind have sometimes vanished by the following year.
Examples of supernova in a Sentence
Monisha Ravisetti, Space.com, 8 Jan. 2026
This is called a supernova explosion.
—Mike Lynch, Twin Cities, 4 Jan. 2026
As the supernova expanded, its blue spectrum waves eventually obscured the kilonova.
—Andrew Paul, Popular Science, 17 Dec. 2025
In this scenario, a supernova births two baby neutron stars that quickly merge, producing a kilonova whose light is partly hidden by expanding supernova debris.
—Neetika Walter, Interesting Engineering, 16 Dec. 2025
See All Example Sentences for supernova
Cite this Entry
“Supernova.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/supernova. Accessed 20 Jan. 2026.
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supernova
noun
