he·​li·​um | \ ˈhē-lē-əm How to pronounce helium (audio) , ˈhēl-yəm \

Definition of helium

: a chemical element of the noble gas group found especially in natural gases and used chiefly for inflating airships and balloons, as a coolant for superconductors, and as a component of inert atmospheres (as in welding) — see Chemical Elements Table

Examples of helium in a Sentence

Recent Examples on the Web In the case of the sun, 99 percent of its energy comes from proton-proton fusion, which can create beryllium, lithium and boron before breaking them down into helium. NBC News, "For the first time, scientists detect the ghostly signal that reveals the engine of the universe," 25 Nov. 2020 Our heads are all tilted upward, our eyes squinting to keep sight of a tiny black dot—a small helium balloon released a few moments ago by Mark West, a tall, silver-haired fellow whose usual easy smile has turned to a tight-lipped frown. Bill Newcott, National Geographic, "The birthplace of the space age isn’t where you think," 22 Sep. 2020 The images of Neptune returned by Voyager 2 and Hubble revealed that the ice giant is a brilliant blue, due to its atmosphere of hydrogen, helium and methane. Ashley Strickland, CNN, "Hubble watches massive storm on Neptune reverse course," 17 Dec. 2020 Like oil and natural gas, helium is a finite resource. Andrew E. Kramer New York Times, Star Tribune, "Big push into helium could have the world on Russia's string," 20 Dec. 2020 The team, which included researchers from New York University Abu Dhabi, also discovered the disk of material was rich in helium. Jennifer Leman, Popular Mechanics, "Astronomers Just Watched a Dead Star Eat Its Neighbor, Which Is Pretty Sick," 5 June 2020 These stars were fashioned only from hydrogen and helium, the cosmos’s rawest materials. Charlie Wood, Quanta Magazine, "The New History of the Milky Way," 15 Dec. 2020 Some researchers are also hopeful that Helium-3, a version of helium that is rare on earth but abundant on the moon, could be used to produce massive amounts of energy via nuclear fusion. Jackie Wattles, CNN, "NASA is paying startups for moon rocks. It's not what you think," 4 Dec. 2020 Researchers know that the sun is at least 98 percent hydrogen and helium, nature’s two lightest and most abundant elements. Charlie Wood, Popular Science, "We still don’t really know what’s inside the sun—but that could change very soon," 30 Nov. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'helium.' 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 helium

1871, in the meaning defined above

History and Etymology for helium

New Latin, from Greek hēlios

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Statistics for helium

Last Updated

19 Feb 2021

Cite this Entry

“Helium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/helium. Accessed 2 Mar. 2021.

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More Definitions for helium



English Language Learners Definition of helium

: a chemical element that is a colorless gas, that is lighter than air, and that is often used to fill balloons


he·​li·​um | \ ˈhē-lē-əm How to pronounce helium (audio) \

Kids Definition of helium

: a very light gaseous chemical element that is found in various natural gases, will not burn, and is used in balloons


he·​li·​um | \ ˈhē-lē-əm How to pronounce helium (audio) \

Medical Definition of helium

: a light colorless nonflammable gaseous element found especially in natural gases and used chiefly for inflating airships and balloons, for filling incandescent lamps, and for cryogenic research symbol He — see Chemical Elements Table

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More from Merriam-Webster on helium

Nglish: Translation of helium for Spanish Speakers

Britannica English: Translation of helium for Arabic Speakers

Britannica.com: Encyclopedia article about helium

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