event horizon

Save This Word!

noun Astronomy.

the boundary around a black hole on and within which no matter or radiation can escape.

QUIZ

QUIZ YOURSELF ON "IS" VS. "ARE"

"Is" it time for a new quiz? "Are" you ready? Then prove your excellent skills on using "is" vs. "are."

Question 1 of 7

IS and ARE are both forms of which verb?

have

TAKE THE QUIZ TO FIND OUT

Origin of event horizon

First recorded in 1970–75

Words nearby event horizon

evensong, even-steven, event, even-tempered, eventful, event horizon, eventide, eventide home, eventing, even-toed ungulate, event planner

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

How to use event horizon in a sentence

But how different would things have been 11 years later, when Scalise attended the Duke event?
Steve Scalise and the Right’s Ridiculous Racial Blame Game|Michael Tomasky|January 2, 2015|DAILY BEAST
This event, know as “Turn Around Tuesday,” enraged many of the demonstrators, especially the young SNCC activists.
Dr. King Goes to Hollywood: The Flawed History of ‘Selma’|Gary May|January 2, 2015|DAILY BEAST
But without any peace talks on the horizon, everyone is now left to their own devices.
In the Middle East, the Two-State Solution Is Dead|Dean Obeidallah|January 2, 2015|DAILY BEAST
In fact, Americans had to wait several hours until film of the event reached New York for it to be broadcast.
Dr. King Goes to Hollywood: The Flawed History of ‘Selma’|Gary May|January 2, 2015|DAILY BEAST

Over dinner, the Knight had mentioned that Scalise had spoken before the EURO event.
GOP Boss Gets Help From ‘White Hate’ Pal|Tim Mak|December 30, 2014|DAILY BEAST
See how those distant peaks rise serenely over the southern horizon!
Blackwood's Edinburgh Magazine, Volume 60, No. 372, October 1846|Various
This would in any event have depressed prices of cotton, even under ordinary conditions.
Readings in Money and Banking|Chester Arthur Phillips
Please advise the surrender as soon as possible in order to give due and solemn publicity to the event.
The Philippine Islands|John Foreman
An estate upon condition is one which depends upon the happening or not happening of some uncertain event.
Assimilative Memory|Marcus Dwight Larrowe (AKA Prof. A. Loisette)
An estate upon condition is one which depends upon the happening or not happening of some event.
Assimilative Memory|Marcus Dwight Larrowe (AKA Prof. A. Loisette)

British Dictionary definitions for event horizon

event horizon

noun

astronomy the surface around a black hole enclosing the space from which electromagnetic radiation cannot escape due to gravitational attraction. For a non-rotating black hole, the radius is proportional to the mass of the black hole

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for event horizon

event horizon

[ ĭ-vĕnt′ ]

A spatial boundary around a black hole inside which gravity is strong enough to prevent all matter and radiation from escaping. The inability of even light to escape this region is what gives black holes their name.