cos·​mol·​o·​gy | \ käz-ˈmä-lə-jē How to pronounce cosmology (audio) \
plural cosmologies

Definition of cosmology

1a : a branch of metaphysics that deals with the nature of the universe
b : a theory or doctrine describing the natural order of the universe
2 : a branch of astronomy that deals with the origin, structure, and space-time relationships of the universe also : a theory dealing with these matters

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Other Words from cosmology

cosmological \ ˌkäz-​mə-​ˈlä-​ji-​kəl How to pronounce cosmological (audio) \ adjective
cosmologically \ ˌkäz-​mə-​ˈlä-​ji-​k(ə-​)lē How to pronounce cosmologically (audio) \ adverb
cosmologist \ käz-​ˈmä-​lə-​jist How to pronounce cosmologist (audio) \ noun

Cosmology and Star Trek

Most religions and cultures include some kind of cosmology to explain the nature of the universe. In modern astronomy, the leading cosmology is still the Big Bang theory, which claims that the universe began with a huge explosion that sent matter and energy spreading out in all directions. One reason why fans watch Star Trek is for the various cosmologies depicted in the show, including different conceptions of space, time, and the meaning of life.

Examples of cosmology in a Sentence

Recent Examples on the Web The prize will be shared between physical cosmologist James Peebles for his contribution to physical cosmology and the astrophysicists Michel Mayor and Didier Queloz, who discovered the first planet circling a star in another galaxy. Jennifer Leman, Popular Mechanics, "Nobel Prize in Physics Awarded to Cosmology, Exoplanet Researchers," 8 Oct. 2019 That said, dark matter and dark energy, with their spooky names, remain mysteries to modern cosmology. Akshat Rathi, Quartz, "Winners of the 2019 Nobel Prize in physics expanded our understanding of the universe," 8 Oct. 2019 According to the prevailing theory of cosmology, every galaxy lies embedded in a vast network of filaments and sheets of hydrogen gas. Adrian Cho, Science | AAAS, "Astronomers map galaxy-feeding hydrogen filaments for the first time," 3 Oct. 2019 The issue may relate to cosmology and the birth of the universe, since expansion out of a Big Bang singularity is much like gravitational collapse into a black hole in reverse. Natalie Wolchover, WIRED, "Space and Time Could Be a Quantum Error-Correcting Code," 6 Jan. 2019 To make sense of the physical laws governing the cosmos, astronomers have tried to measure one of the most important numbers in cosmology, the Hubble constant, which describes how quickly this expansion is happening and the universe’s age in turn. Michael Greshko, National Geographic, "The universe might be acting weird. Cosmic 'lenses' may help reveal why.," 12 Sep. 2019 Ultimately the concept of time crystals offers a chance for progress both theoretically—in terms of understanding cosmology and black holes from another perspective—and practically. Frank Wilczek, Scientific American, "The Exquisite Precision of Time Crystals," 16 Oct. 2019 The choice to recognize Peebles’s cosmology theories sparked particular anger, because the woman who proved the existence of dark matter, Vera Rubin, was never given the award. Sarah Kaplan, Washington Post, "Nobel Prize in physics awarded for research on exoplanets and the structure of the universe," 8 Oct. 2019 The expansion rate, called the Hubble constant , is one of the most important numbers in cosmology. NBC News, "The universe may be billions of years younger than we thought," 12 Sep. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'cosmology.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of cosmology

circa 1656, in the meaning defined at sense 1a

History and Etymology for cosmology

New Latin cosmologia, from Greek kosmos — see cosmic + New Latin -logia -logy

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Learn More about cosmology

Time Traveler for cosmology

Time Traveler

The first known use of cosmology was circa 1656

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Statistics for cosmology

Last Updated

13 Dec 2019

Cite this Entry

“Cosmology.” The Dictionary, Merriam-Webster Inc., Accessed 15 December 2019.

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More Definitions for cosmology


How to pronounce cosmology (audio)

English Language Learners Definition of cosmology

: the scientific study of the origin and structure of the universe

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More from Merriam-Webster on cosmology

Nglish: Translation of cosmology for Spanish Speakers

Britannica English: Translation of cosmology for Arabic Speakers Encyclopedia article about cosmology

Comments on cosmology

What made you want to look up cosmology? Please tell us where you read or heard it (including the quote, if possible).


delight or enjoyment

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