dark energy

American  

[dahrk en-er-jee] / ˈdɑrk ˈɛn ər dʒi /

noun

1. a hypothetical form of energy whose negative pressure counteracts gravity and is assumed to be responsible for the universe expanding at an accelerating rate.

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dark energy Scientific  

1. A form of energy hypothesized to reside in the structure of space itself, responsible for the accelerating expansion of the universe. Dark energy theoretically counterbalances the kinetic energy of the universe's expansion, entailing that that the universe has no inherent curvature, as astronomical observations currently suggest. Dark energy appears to account for 73 percent of all the energy and matter in the universe.

2. See also big bang

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dark energy Cultural  

1. An as yet unknown and unidentified form of energy that pervades the universe and produces a force that counteracts the gravitational attraction between galaxies.

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Discover More

Dark energy is thought to be responsible for the accelerating universe.

Etymology

Origin of dark energy

First recorded in 1995–2000

Example Sentences

But put them together and contradictions appear – especially when it comes to black holes, dark matter, dark energy and the origins of the cosmos.

From Science Daily • Jun. 18, 2026

"By proving our measurements are correct, we can get back to trying to understand what dark energy actually is, rather than wondering if it exists at all."

From Science Daily • Jun. 13, 2026

“Living in the deepest corners of our vast cosmos or our mathematical constructs,” the authors write, are still-unsolved scientific mysteries, including dark matter and dark energy.

From The Wall Street Journal • May 19, 2026

With the full dataset now in hand, researchers have a much stronger foundation to test long-standing ideas about the balance between dark energy and matter.

From Science Daily • Apr. 28, 2026

It appears that the universe may not only be filled with dark matter, but with dark energy.

From "A Short History of Nearly Everything" by Bill Bryson