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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.


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


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.


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.

See Examples For:

The Lambda refers to the cosmological constant, which is also known as dark energy.

From Science Daily Aug. 18, 2026

Its two main professional telescopes carry out wide-sky astronomical surveys that help scientists investigate galaxies, dark energy, and the large-scale structure of the cosmos.

From Science Daily Aug. 10, 2026

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

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

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