cos·mos | \ˈkäz-məs, senses 1 & 2 also -ˌmōs, -ˌmäs \

Definition of cosmos 

1a : universe sense 1

b(1) : an orderly harmonious systematic universe — compare chaos

(2) : order, harmony

2 : a complex orderly self-inclusive system

3 plural cosmos\ˈkäz-məs, -məz\ also cosmoses\ˈkäz-mə-səz \ [ 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

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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

Additional sky surveys, and refined measurements of the farthest disk stars, will continue to dial in the border of our galactic neighborhood of the cosmos. Jay Bennett, Popular Mechanics, "The Milky Way Galaxy Might Be Twice as Wide as Astronomers Thought," 13 June 2018 But when combined to help build complex protein chains that form cells, some of which are neurons that generate thoughts in brains, awareness of the cosmos and even self-awareness are possible, given time. Scientific American, "Readers Respond to the March 2018 Issue," 13 Mar. 2018 Angelica, coreopsis, cosmos, and sweet alyssum will bring lacewings to your garden. The Editors Of Organic Life, Good Housekeeping, "10 Insects You Should Actually Want Around Your Plants," 11 May 2016 If telescopes are our eyes on the cosmos, neutrino detectors might be our ears, or nose: Their signals reveal complementary information. Sophia Chen, WIRED, "What's a Blazar? A Galactic Bakery for Cosmic Rays," 12 July 2018 At curtain, ethereal lights rise on a shadowy cosmos represented by stage fog, evocative costumes, music and free-style dance movement (one cast member twirls a spinning globe) as a prelude to video clips from interviews with real people. Patti Restivo, Howard County Times, "In 'Making Advances,' a staged revolution," 14 June 2018 Observing these photons led to startling discoveries about our cosmos, from the Big Bang to the existence of dark matter. Eoin O'carroll, The Christian Science Monitor, "Neutrino demonstration heralds a new way of observing the cosmos," 12 July 2018 Whenever researchers invent a new method, unprecedented information is collected and people’s understanding of the cosmos deepens. Scientific American, "Astronomy at the Speed of Light," 3 July 2018 Want to keep expanding your consciousness about the cosmos? Shannon Stirone, WIRED, "Space Photos of the Week: Scientists Are Seeing Red Over Jupiter’s Spot," 30 June 2018

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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Phrases Related to cosmos

the cosmos

Statistics for cosmos

Last Updated

26 Sep 2018

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Time Traveler for cosmos

The first known use of cosmos was in 1596

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English Language Learners Definition of cosmos

the 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

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Comments on cosmos

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


to reject or criticize sharply

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