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
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Each prospect is horrifying in its own way, but the looming sense of an event horizon has produced a golden age of writing and scholarship on the moral question of where, why, and how to draw the species boundary. Gideon Lewis-Kraus, New Yorker, 13 June 2025 This is because unlike black hole evaporation, which is driven by the presence of an event horizon, this more general form of decay is driven by the curvature of spacetime itself. Sharmila Kuthunur, Space.com, 15 May 2025 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 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

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Cite this Entry

“Event horizon.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/event%20horizon. Accessed 19 Jun. 2025.

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