dark energy
Americannoun
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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.
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See also big bang
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
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
The invisible dark matter and dark energy that make up more than 95% of the Universe.
From BBC ● Jul. 27, 2026
In another, we showed how dark energy might emerge too.
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
Recent observations have raised questions that could point toward new physics, including the effects of massive neutrinos, modified gravity, and evolving dark energy.
From Science Daily ● Jun. 11, 2026
As Frank watched, a bolt of dark energy ripped through the air, rocking the ship and sending a cold shockwave across the landscape.
From "The House of Hades" by Rick Riordan
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