helium

noun

he·li·um ˈhē-lē-əm

ˈhēl-yəm

: a chemical element of the noble gas group with atomic number 2 that is 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)

—often used before another noun

helium balloons

helium gas

see Chemical Elements Table

Examples of helium in a Sentence

Recent Examples on the Web In 50 years a kilogram of plutonium will amass around 0.2 liter of helium. —

Sarah Scoles, Scientific American, 14 Nov. 2023 Hanging above that was a hair dryer that had been used for warming up equipment that had been cooled in liquid helium. —

Dennis Overbye Hiroko Masuike, New York Times, 4 Sep. 2023 The subsequent radiation, pressure, and energy then fuses two types of heavy hydrogen, tritium and deuterium, to form helium. —

Time, 24 July 2023 But maybe even more importantly, these materials were the first superconductors above the boiling point of liquid nitrogen, which is cheaper and easier to handle than liquid helium. —

Darren Orf, Popular Mechanics, 15 Aug. 2023 Newsletter Sign up for our email newsletter for the latest science news Deep inside stars, fusion reactions combine hydrogen atoms to form helium and release a burst of energy. —

Matt Hrodey, Discover Magazine, 2 Aug. 2023 When the Earth was formed out of the primordial solar nebula, light elements like hydrogen, helium and lithium were mostly left out of the planet's materials (beyond hydrogen in water). —

Erik Klemetti, Discover Magazine, 20 Sep. 2023 The complexity of these refrigerators is greatest at the coldest stage, which involves mixing different isotopes of liquid helium. —

IEEE Spectrum, 12 Sep. 2023 Inside this tube is a gas, such as helium or argon, with a wire running along the axis of the tube. —

WIRED, 8 Sep. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'helium.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

New Latin, from Greek hēlios

First Known Use

1871, in the meaning defined above

Time Traveler

The first known use of helium was in 1871

See more words from the same year

Cite this Entry

Style

“Helium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/helium. Accessed 2 Dec. 2023.

Copy Citation

Kids Definition

helium

noun

he·li·um ˈhē-lē-əm

: a light colorless nonflammable element that is found in various natural gases and is used especially to blow up balloons see element

Medical Definition

helium

noun

he·li·um ˈhē-lē-əm

: 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