black·​body ˈblak-ˈbä-dē How to pronounce blackbody (audio)
: an ideal body or surface that completely absorbs all radiant energy falling upon it with no reflection and that radiates at all frequencies with a spectral energy distribution dependent on its absolute temperature

Examples of blackbody in a Sentence

Recent Examples on the Web In brief, the geometry dictates that 100% of the radiation originating from the blackbody at A will land on and be absorbed by the blackbody at B because both A and B are the foci of ellipses E1 and E2. Quanta Magazine, 22 May 2020 It’s also used to calculate the distribution of energies for a blackbody (an object that gives off light due only to its temperature), and for the uncertainty principle that gives a relation between measurements of position and momentum. Rhett Allain, Wired, 8 Oct. 2021 Moreover, this radiation should have the spectrum of a perfect blackbody, with only tiny imperfections at the ~0.01% level or less. Ethan Siegel, Forbes, 6 May 2021 But more sensitive measurements should undoubtedly reveal small deviations from the blackbody curve that COBE measured. Quanta Magazine, 30 June 2015 That would have shifted the CMB’s spectrum away from a blackbody. Quanta Magazine, 30 June 2015 That’s important, said John Mather, an astrophysicist at NASA Goddard who won a Nobel Prize in 2006 for measuring the CMB’s blackbody spectrum with COBE. Quanta Magazine, 30 June 2015 Two of the assumptions used to obtain the rules of blackbody radiation provide loopholes. Chris Lee, Ars Technica, 11 Sep. 2018 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'blackbody.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1712, in the meaning defined above

Time Traveler
The first known use of blackbody was in 1712

Dictionary Entries Near blackbody

Cite this Entry

“Blackbody.” Dictionary, Merriam-Webster, Accessed 28 Sep. 2023.

Kids Definition


black·​body ˈblak-ˈbäd-ē How to pronounce blackbody (audio)
: a body or surface that absorbs all radiant energy falling upon it with no reflection

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