aurora

noun
au·​ro·​ra | \ ə-ˈrȯr-ə How to pronounce aurora (audio) , ȯ-\
plural auroras or aurorae\ -​(ˌ)ē How to pronounce aurorae (audio) \

Definition of aurora

 (Entry 1 of 2)

1 : dawn
2 capitalized : the Roman goddess of dawn — compare eos
3 : a luminous phenomenon that consists of streamers or arches of light appearing in the upper atmosphere of a planet's magnetic polar regions and is caused by the emission of light from atoms excited by electrons accelerated along the planet's magnetic field lines

Aurora

geographical name
Au·​ro·​ra | \ ə-ˈrȯr-ə How to pronounce Aurora (audio) , ȯ-\

Definition of Aurora (Entry 2 of 2)

1 city in north central Colorado east of Denver population 325,078
2 city west of Chicago in northeastern Illinois population 197,899
3 town north of Toronto in southeastern Ontario, Canada population 53,203

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Other Words from aurora

Noun

auroral \ -​əl How to pronounce auroral (audio) \ adjective
aurorean \ -​ē-​ən How to pronounce aurorean (audio) \ adjective

Synonyms & Antonyms for aurora

Synonyms: Noun

cockcrow, dawn, dawning, day, daybreak, daylight, light, morn, morning, sun, sunrise, sunup

Antonyms: Noun

nightfall, sundown, sunset

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Examples of aurora in a Sentence

Noun

a gorgeous pink aurora aroused us out of our slumber

Recent Examples on the Web: Noun

Because the phenomenon was occurring outside the usual geographic range for frequent auroras, citizen scientists played a particularly valuable role in understanding STEVE, MacDonald said. Sarah Lewin, Space.com, "Meet 'Steve,' the Aurora-Like Mystery Scientists Are Beginning to Unravel," 14 Mar. 2018 Now, a new purplish aurora is joining the show, stretching from east to west at lower latitudes. Katie Langin, Science | AAAS, "Top stories: Honoring Stephen Hawking, excavating eruptions, and solving an ancient skull mystery," 16 Mar. 2018 Scientists have determined that streaks of purple captured by amateur photographers are not auroras at all, but are rather an entirely new type of celestial phenomenon. David Grossman, Popular Mechanics, "Meet STEVE: The Light Phenomenon That's Not Aurora Borealis," 22 Aug. 2018 But these auroras are not the only thing lighting up the night. David Grossman, Popular Mechanics, "Meet STEVE: The Light Phenomenon That's Not Aurora Borealis," 22 Aug. 2018 Those on the aurora-borealis-or-bust trail will be spoiled for choice in Finland. Cnt Editors, Condé Nast Traveler, "The 30 Most Romantic Adventures," 8 Feb. 2018 Such a storm can also amplify Earth's auroras, making them visible in lower latitudes than usual. Samantha Mathewson, Space.com, "'Hole' in the Sun Spawns Powerful Solar Wind; Could Amp Up Auroras," 10 Apr. 2018 Those particles will be captured by the magnetosphere and make it to the ionosphere as artificial aurora. Avery Thompson, Popular Mechanics, "A Group of Scientists Want to Launch a Satellite to Make an Artificial Aurora," 29 Oct. 2018 Earth's magnetic field channels these particles toward the planet's poles, which explains why the auroras are usually restricted to high latitudes. Mike Wall, Space.com, "Hole in Sun's Atmosphere Amps Up Northern Lights," 11 Sep. 2018

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

Noun

14th century, in the meaning defined at sense 1

History and Etymology for aurora

Noun

Latin — more at east

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Statistics for aurora

Last Updated

13 Mar 2019

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Time Traveler for aurora

The first known use of aurora was in the 14th century

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More from Merriam-Webster on aurora

Rhyming Dictionary: Words that rhyme with aurora

Thesaurus: All synonyms and antonyms for aurora

Spanish Central: Translation of aurora

Britannica.com: Encyclopedia article about aurora

Comments on aurora

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