helium

[ hee-lee-uhm ]

noun

an inert, gaseous element present in the sun's atmosphere and in natural gas, and also occurring as a radioactive decomposition product, used as a substitute for flammable gases in dirigible balloons. Symbol: He; atomic weight: 4.0026; atomic number: 2; density: 0.1785 grams/liter at 0°C and 760 millimeters pressure.

Origin of helium

First recorded in 1875–80; from New Latin, from Greek hḗli(os) “the sun” + New Latin -ium noun suffix; see -ium

Words Nearby helium

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use helium in a sentence

The team behind some of the earlier measurements is now back with a new one, this one tracking the behavior of a muon orbiting a helium nucleus.
Unstable helium adds a limit on the ongoing saga of the proton’s size | John Timmer | January 27, 2021 | Ars Technica
They could change their altitude to catch different air currents by either pumping air in, or out, of a smaller balloon that was inside the larger helium vessel.
RIP Loon, Google’s balloon-based cellular network | Rob Verger | January 22, 2021 | Popular-Science
These stars were fashioned only from hydrogen and helium, the cosmos’s rawest materials.
The New History of the Milky Way | Charlie Wood | December 15, 2020 | Quanta Magazine
The typical Macy’s parade balloon may use around 12,000 cubic feet of helium, while global consumption is on the order of 6 billion cubic feet per year.
The Macy’s Thanksgiving Day Parade has one star that always rises to the top | Erik Olsen | November 25, 2020 | Popular-Science
The helium absorbed heat from the LEDs as it wound through the channel and expanded until it was finally released through a small nozzle.
A solar-powered rocket might be our ticket to interstellar space | WIRED | November 21, 2020 | Ars Technica

She added in the high-pitched, over-enunciated voice, like she was alternating between sucking on helium and a bong.
SNL’s Kim Kardashian Konundrum: Why Nasim Pedrad’s Exit Hurts So Much | Jason Lynch | September 26, 2014 | THE DAILY BEAST
Previously a big, fat tank of liquid helium was needed for the task.
Up to a Point: A 'Space Corvette' in Every Garage | P. J. O’Rourke | September 6, 2014 | THE DAILY BEAST
So of course, Jimmy Fallon took the opportunity to ruin it by forcing Freeman to inhale helium and pitch up his voice.
Viral Video of the Day: Morgan Freeman Sucks Helium | Alex Chancey | July 25, 2014 | THE DAILY BEAST
Especially when the one you love has a voice like nails on a helium-soaked chalkboard.
Chucky, the Possessed Doll, on His Favorite Kills—and Katherine Heigl | Chucky | October 31, 2013 | THE DAILY BEAST
After he inhaled sulfur hexafluoride, a compound that acts like helium, his voice got very deep.
The Anger Over ‘Tranny,’ From Neil Patrick Harris to RuPaul to Dan Savage | Tricia Romano | January 30, 2012 | THE DAILY BEAST
What bug in the new helium process might account for this delay?
Bread Overhead | Fritz Reuter Leiber
There was only one thing to do, there being only one other gas comparable in lightness to helium.
Bread Overhead | Fritz Reuter Leiber
An atom of lithium-7 plus an atom of hydrogen-1 yields two atoms of helium-4 and plenty of energy.
Unwise Child | Gordon Randall Garrett
He turned the dial to emergency maximum and gulped precious liters of oxygen-helium mixture.
Tight Squeeze | Dean Charles Ing
When they opened the sample chamber, they got a blast of high-pressure helium right in the face.
The Bramble Bush | Gordon Randall Garrett

British Dictionary definitions for helium

helium

/ (ˈhiːlɪəm) /

noun

a very light nonflammable colourless odourless element that is an inert gas, occurring in certain natural gases: used in balloons and in cryogenic research. Symbol: He; atomic no: 2; atomic wt: 4.002602; density: 0.1785 kg/m³; at normal pressures it is liquid down to absolute zero; melting pt: below –272.2°C; boiling pt: –268.90°C: See also alpha particle

Origin of helium

C19: New Latin, from helio- + -ium; named from its having first been detected in the solar spectrum

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for helium

helium

[ hē′lē-əm ]

A very lightweight, colorless, odorless element in the noble gas group. Helium occurs in natural gas, in radioactive ores, and in small amounts in the atmosphere. It has the lowest boiling point of any substance and is the second most abundant element in the universe. Helium is used to provide lift for balloons and blimps and to create artificial air that will not react chemically. Atomic number 2; atomic weight 4.0026; boiling point -268.9°C; density at 0°C 0.1785 gram per liter. See Periodic Table.

word history

The second most abundant element in the universe after hydrogen, Helium (symbol He) is a colorless, odorless, nonmetallic gas that is produced abundantly by the nuclear fusion in all stars and is found in smaller amounts on Earth. It was discovered by the British scientist-and founding editor of the journal Nature-Joseph Norman Lockyer in 1868, while he was studying a solar eclipse with a spectroscope, an instrument that breaks light up into a spectrum. If an element is heated up enough to glow, the emitted light produces a unique spectrum when refracted through a prism. Lockyer noticed that the spectrum of the Sun's corona, which is visible only during a solar eclipse, contained lines produced by an unknown element. He named the element helium from helios, the Greek word for sun. Helios gives us many other words pertaining to the Sun, such as heliocentric and perihelion.

Cultural definitions for helium

helium

A chemical element, usually found in the form of a gas, in which two electrons are in orbit, and the nucleus consists of two protons and two neutrons. Its symbol is He.

Notes for helium

Helium is the best known of the inert gases.

Notes for helium

Because it is lighter than air, helium is used to fill balloons.

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