cos·​mos | \ ˈkäz-məs How to pronounce cosmos (audio) , senses 1 & 2 also -ˌmōs, -ˌmäs How to pronounce cosmos (audio) \

Definition of cosmos

b(1) : an orderly harmonious systematic universe — compare chaos
(2) : order, harmony
2 : a complex orderly self-inclusive system
3 plural cosmos\ ˈkäz-​məs How to pronounce cosmos (audio) , -​məz \ also cosmoses\ ˈkäz-​mə-​səz How to pronounce cosmos (audio) \ [New Latin, genus name, from Greek kosmos] : any of a genus (Cosmos) of tropical American composite herbs especially : a widely cultivated tall annual (C. bipinnatus) with yellow or red disks and showy ray flowers

Illustration of cosmos

Illustration of cosmos

cosmos 3

Cosmos and the Universe

Cosmos often simply means "universe". But the word is generally used to suggest an orderly or harmonious universe, as it was originally used by Pythagoras in the 6th century B.C. Thus, a religious mystic may help put us in touch with the cosmos, and so may a physicist. The same is often true of the adjective cosmic: Cosmic rays (really particles rather than rays) bombard us from outer space, but cosmic questions come from human attempts to find order in the universe.

Examples of cosmos in a Sentence

the origins of the cosmos an essay that ponders the place of humankind in the vast cosmos
Recent Examples on the Web Stars eventually expend their energy and burst across the cosmos, with much of that matter becoming the material of other stars, other worlds. Scott Sayare, Harper's Magazine, 23 Nov. 2021 Humans Are On Track to Export Our Environmental Problems to Space Now that the cosmos is turning into the playground for entrepreneurs, the outdated legal spacescape needs to directly address space pollution. Paola Rosa-aquino, Wired, 18 Nov. 2021 Gravitational waves cut through the cosmos’ largest masses with impunity. Bruce Dorminey, Forbes, 10 Nov. 2021 The odds are good, given how many stars are sprinkled across the cosmos. Marina Koren, The Atlantic, 4 Nov. 2021 By deducing the expansion rate from Planck’s cosmic microwave background data, researchers could estimate how many types of neutrinos filled the young cosmos. Quanta Magazine, 28 Oct. 2021 The sequence does contextualize pandemic experience within the show’s metaphysical landscape, but the specificity of the responses (missed the gym!) can be a jarring match for the cosmos-scrutinizing that follows. Washington Post, 26 Oct. 2021 In addition to exploring the cosmos, its perch at 1,134 feet offers panoramic views of the Los Angeles Basin and the iconic Hollywood sign atop Mount Lee. Andrea Mchugh And Julie Loffredi, USA TODAY, 15 Oct. 2021 Space is a refuge, a frontier, or an untapped market; Earth must be saved, or escaped, or writ large across the cosmos. New York Times, 7 Oct. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'cosmos.' 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 cosmos

1596, in the meaning defined at sense 1a

History and Etymology for cosmos

Greek kosmos

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Last Updated

27 Nov 2021

Cite this Entry

“Cosmos.” Dictionary, Merriam-Webster, Accessed 1 Dec. 2021.

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More Definitions for cosmos



English Language Learners Definition of cosmos

: the universe especially when it is understood as an ordered system
: a tall plant that has usually white, pink, or red flowers


cos·​mos | \ ˈkäz-məs, 1 is also -ˌmōs, -ˌmäs \

Kids Definition of cosmos

1 : the universe especially as thought of as an orderly system
2 : a tall garden plant related to the daisies that has showy white, pink, or rose-colored flower heads

More from Merriam-Webster on cosmos

Nglish: Translation of cosmos for Spanish Speakers

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


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