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

Also indicative of a dense shroud of gas were signs of fluorescence and helium-absorbing radiation. —Robert Lea, Space.com, 10 June 2026

The helium-balloon hype of potentially going undefeated through the final three rounds of the playoffs has been punctured and now it’s gone for good. —Hannah Keyser, CNN Money, 9 June 2026

This reaction results in a helium nucleus and releases a neutron and radiation. —ArsTechnica, 9 June 2026

That’s continuing ongoing supply crunches of helium, fertilizer, natural gas and oil, the effects of which are still winding their way through the global economy and the worst may not be felt for weeks, even if traffic were to reopen today. —Alex Knapp, Forbes.com, 5 June 2026

Word History

Etymology

New Latin, from Greek hēlios

First Known Use

1871, in the meaning defined above

Rhymes for helium

• cilium

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