aurora

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

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, 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 \ adjective
aurorean \-​ē-​ən \ 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

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 MacDonald led a team who observed the aurora by sending one of the European Space Agency’s Swarm satellites through it. Krista Trinder, National Geographic, "Meet ‘Steve,’ a Totally New Kind of Aurora," 14 Mar. 2018 Falcke says the team will study solar flares, the aurora of Jupiter, and the galaxy's radio emissions. Daniel Clery, Science | AAAS, "China’s moon mission will probe cosmic dark ages," 16 May 2018 To get an idea of what’s in store, these bright bands of green auroras were captured just after midnight on Tuesday over Lake Superior near Copper Harbor, Michigan. Lyndsey Matthews, Country Living, "There's Another Chance to See the Northern Lights Tonight," 11 Apr. 2018 This stream of particles can mingle with Earth’s magnetic field, causing geomagnetic storms that mess with our satellites and power grid and create auroras. Loren Grush, The Verge, "The NASA spacecraft that will journey to the Sun just got its super deluxe heat shield," 8 July 2018 Elders tell their stories and a narrator tells us of the sun's essential role in creating the aurora. Ned Rozell, Anchorage Daily News, "Where myth meets science: The northern lights in Nuiqsut, seen inside a portable planetarium," 21 Apr. 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

4 Dec 2018

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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

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