xe·​non | \ ˈzē-ˌnän How to pronounce xenon (audio) , ˈze- How to pronounce xenon (audio) \

Definition of xenon

: a heavy colorless and relatively inert gaseous element that occurs in air as about one part in 20 million and is used especially in specialized electric lamps (such as flashtubes) and in scientific research — see Chemical Elements Table

Examples of xenon in a Sentence

Recent Examples on the Web

Pretty much nothing reacts with xenon, especially a mile underground, making it the ideal dark matter detector. Avery Thompson, Popular Mechanics, "Dark Matter Scientists Observe the Rarest Event in History," 27 Apr. 2019 No xenon to futz with, or wings to flap, or rotors to spin. Matt Simon, WIRED, "An Itty-Bitty Robot That Lifts Off Like a Sci-Fi Spaceship," 4 July 2019 One of those is the XENON observatory, which is essentially a giant tank containing 3.5 tons of liquid xenon sitting in a laboratory nearly a mile underground. Avery Thompson, Popular Mechanics, "Dark Matter Scientists Observe the Rarest Event in History," 27 Apr. 2019 Then wait for a passing WIMP to bang into a xenon atom’s nucleus. Quanta Magazine, "In the Deep, a Drive to Find Dark Matter," 20 Dec. 2016 One of Brown’s areas of study is trying to capture dark matter interactions with normal matter in the form of liquid xenon isotopes. Joe Lindsey, Popular Mechanics, "Filling the Void: What Is Dark Matter?," 28 May 2019 His prototype uses lithium ions, which are much lighter than the xenon ions Dawn used, and therefore need less energy to attain higher velocities. Corey S. Powell, Discover Magazine, "These New Technologies Could Make Interstellar Travel Real," 13 Mar. 2019 Mercury is much heavier than either xenon or krypton, so spacecraft carrying them would be able to generate more thrust. Avery Thompson, Popular Mechanics, "Space Startup Apollo Fusion Wants To Use Mercury as a Fuel—Report," 20 Nov. 2018 An electric propulsion engine—such as a Hall thruster that ionizes xenon gas—has a high specific impulse, as much as 10 times that of NTP. Jay Bennett, Popular Mechanics, "NASA's Nuclear Thermal Engine Is a Blast From the Cold War Past," 21 Feb. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'xenon.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of xenon

1898, in the meaning defined above

History and Etymology for xenon

Greek, neuter of xenos strange

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Statistics for xenon

Last Updated

12 Aug 2019

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Time Traveler for xenon

The first known use of xenon was in 1898

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English Language Learners Definition of xenon

: a chemical element that is a colorless gas and that is used especially in electric lights


xe·​non | \ ˈzē-ˌnän How to pronounce xenon (audio) , ˈzen-ˌän How to pronounce xenon (audio) \

Medical Definition of xenon

: a heavy, colorless, and relatively inert gaseous element that occurs in air as about one part in 20 million by volume symbol Xe — see Chemical Elements Table

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More from Merriam-Webster on xenon

Rhyming Dictionary: Words that rhyme with xenon

Spanish Central: Translation of xenon

Nglish: Translation of xenon for Spanish Speakers

Britannica.com: Encyclopedia article about xenon

Comments on xenon

What made you want to look up xenon? Please tell us where you read or heard it (including the quote, if possible).


authorized for issue (as a bond)

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