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cosmic microwave background

cosmic microwave background noun: faint thermal radiation that pervades all space and is thought to be the remnants of the Big Bang, produced during the epoch of recombination.

cosmic microwave background: faint thermal radiation that pervades all space and is thought to be the remnants of the Big Bang,...
Image: ESA and the Planck Collaboration, CC BY 4.0, via Wikimedia Commons

Noun

cosmic microwave background (uncountable, abbreviation CMB)

  1. Faint thermal radiation that pervades all space and is thought to be the remnants of the Big Bang, produced during the epoch of recombination.
    • Holonyms: cosmic background, cosmic background radiation < electromagnetic radiation < radiation

Forms of cosmic microwave background

abbreviationCMB

Origin of cosmic microwave background

It was originally called the primeval fireball.

Questions about cosmic microwave background

What does cosmic microwave background mean?
Cosmic microwave background means faint thermal radiation that pervades all space and is thought to be the remnants of the Big Bang, produced during the epoch of recombination.
What part of speech is cosmic microwave background?
Cosmic microwave background is a noun.

Words near cosmic microwave background in the dictionary

  1. cosmic joker
  2. cosmic jokers
  3. cosmic latte
  4. cosmic light horizon
  5. cosmic light horizons
  6. cosmic microwave background
  7. cosmic neutrino background
  8. Cosmic Owl
  9. cosmic radiation
  10. cosmic ray
  11. cosmic rays

Source and license

Adapted from Wiktionary: cosmic microwave background (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

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Pronunciation audio from Wikimedia Commons, each file under its own free license: LL-Q1860 (eng)-Flame, not lame-cosmic microwave background.wav.

Cite this entry: “cosmic microwave background.” Word.ws, https://word.ws/cosmic_microwave_background. Based on Wiktionary, CC BY-SA 4.0.