event horizon

noun

: the surface of a black hole : the boundary of a black hole beyond which nothing can escape from within it

Examples of event horizon 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.
Near a black hole's event horizon, however, the intense gravitational field prevents such annihilation. Sharmila Kuthunur, Space.com, 15 May 2025 The film provides no answers but plunges nightmarishly onward into the questions, changing form at will as though, here at the event horizon of global meltdown, all the regular rules and codes have started to warp and bend. Jessica Kiang, Variety, 15 May 2025 Considered from far enough away, well beyond the event horizon—that pivotal region within which neither matter nor light can escape—a black hole can be modeled as a particlelike point with mass and spin, albeit one that generates gravitational rather than electromagnetic waves. Ramin Skibba, Scientific American, 13 May 2025 For example, the inside and outside of a black hole are decoupled by a boundary called the event horizon. Lyndie Chiou, Wired News, 20 Apr. 2025 See All Example Sentences for event horizon

Word History

First Known Use

1956, in the meaning defined above

Time Traveler
The first known use of event horizon was in 1956

Browse Nearby Words

Cite this Entry

“Event horizon.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/event%20horizon. Accessed 29 May. 2025.

Last Updated: - Updated example sentences
Love words? Need even more definitions?

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