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

The most massive stars, the ones that form in the molecular gas clouds brought together by gravity, burn hydrogen into helium, helium into carbon, and then build up heavier elements like oxygen, neon, magnesium, sulphur, silicon, and even iron, cobalt, and nickel in their cores. —Big Think, 27 Nov. 2025

As harsh winds whipped outside, organizers chose to ground the balloons for the first time since the helium shortage during WWII. —Randall Colburn, Entertainment Weekly, 27 Nov. 2025

At the time, the balloons were released at the end of the parade after valves were installed, allowing the helium to release slowly. —Alyssa Davis, PEOPLE, 27 Nov. 2025

The public gets to watch Macy’s and Messer workers, including the folks from Kansas, fill the giant balloons with helium along Central Park West. —Lisa Gutierrez, Kansas City Star, 24 Nov. 2025

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