cosmos
Americannoun
plural
cosmos, cosmoses-
the world or universe regarded as an orderly, harmonious system.
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a complete, orderly, harmonious system.
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order; harmony.
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any composite plant of the genus Cosmos, of tropical America, some species of which, as C. bipannatus and C. sulphureus, are cultivated for their showy ray flowers.
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(initial capital letter) Also Kosmos. one of a long series of Soviet satellites that have been launched into orbit around the earth.
noun
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the world or universe considered as an ordered system
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any ordered system
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harmony; order
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any tropical American plant of the genus Cosmos, cultivated as garden plants for their brightly coloured flowers: family Asteraceae (composites)
noun
Usage
What is the cosmos flower? A cosmos is a flower with brightly colored, raylike petals. The name cosmos can be used for any plant in the genus Cosmos. The plural can be cosmos or cosmoses. Cosmoses are popular in gardens. Two of the best-known species are Cosmos bipannatus and Cosmos sulphureus (known as sulphur cosmos), both of which are cultivated for their flowers. Cosmos flowers vary widely in color. Varieties include yellow, orange, pink, and purple. In some varieties, the petals are notched at the tips. Cosmos are one of the October birth flowers (a flower that’s associated with a particular month in the same way as a birthstone). Example: The display at the botanical garden featured flashy orange cosmoses.
Etymology
Origin of cosmos
First recorded in 1150–1200; Middle English, from Greek kósmos “order, form, arrangement, the world or universe”
Explanation
The cosmos is the sum total of everything — pretty big. It's hard to wrap your mind around the cosmos, as it extends far beyond the Milky Way, or far-off galaxies, or even our own universe. Cosmos is originally a Greek word, meaning both "order" and "world," because the ancient Greeks thought that the world was perfectly harmonious and impeccably put in order. We now use cosmos without the idea of perfect order. Now it means, "all of creation," and particularly on the scale of the stars, the planets, the black holes, the other universes, and all the stuff we don't know about. It's also, totally separately, the name of a pretty, flowering Mexican herb.
Vocabulary lists containing cosmos
Elements of the Universe: Cosm, Cosmo ("Universe")
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Oh, My Stars! The Language of Outer Space
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Space Science (Astronomy) - Introductory
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Dr Stephen Grimes, from the university's school of geography, earth and environment said: "This project will transform mundane rooftops and gutters all around Plymouth into portals to the cosmos."
From BBC • Apr. 4, 2026
Someone must venture to the far side of the cosmos to investigate whatever factor is stopping the solar Pac-Man out there, in hopes of bringing it back to our solar system and saving our sun.
From The Wall Street Journal • Mar. 18, 2026
Neutrinos are among the most common particles in the cosmos.
From Science Daily • Mar. 3, 2026
With a wave of her wand and a few magic words, Evie disappears under the snow-covered ground outside her family’s home and is transported to a stunning underwater cosmos.
From The Wall Street Journal • Feb. 20, 2026
Slipher was the first to notice this effect with light and to realize its potential importance for understanding the motions of the cosmos.
From "A Short History of Nearly Everything" by Bill Bryson
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.