Main definitions of aurora in US English:

: aurora1Aurora2Aurora3

aurora1

noun

  • 1A natural electrical phenomenon characterized by the appearance of streamers of reddish or greenish light in the sky, usually near the northern or southern magnetic pole.

    The effect is caused by the interaction of charged particles from the sun with atoms in the upper atmosphere. In northern and southern regions it is respectively called aurora borealis or Northern Lights and aurora australis or Southern Lights

    • ‘And then last week another big storm that caused auroras and beautiful geo magnetic activity all over the world.’
    • ‘Experts used to think it was just a matter of the air being heated by particles and electric currents in the regions around the poles, where auroras occur.’
    • ‘The Hubble Space Telescope has spotted auroras near the poles of both Saturn and Jupiter.’
    • ‘Gaps in the magnetosphere also allow for one of Earth's most beautiful, eerie phenomena: the aurora borealis, or northern lights.’
    • ‘The eventual physical effects of the storm were minimal - auroras were visible in Boston and other northern U.S. cities, but no satellites or power grids had major failures.’
    • ‘He expanded on their work by pulling in historical records of auroras, naked-eye sunspots, and eclipses.’
    • ‘In the southern hemisphere, sky watchers saw the aurora australis over New Zealand, Australia, and South Africa.’
    • ‘Birkeland's experiments failed to account for one of the most important traits of auroras: they are common around the polar regions but exceedingly rare at the poles themselves.’
    • ‘Although the solar wind produces beautiful auroras, it can also cause a variety of undesirable consequences.’
    • ‘Bound to the Earth, our only naturally occurring experience with space weather comes from what we can see with our eyes: eclipses, comets, auroras, and sunspots.’
    • ‘As it is, auroras on Earth follow magnetic lines of force that converge at the north and south magnetic poles.’
    • ‘A typical example of how both missions will co-operate is the study of the magnetic substorms producing the bright aurorae.’
    • ‘This causes the phenomenon called the northern lights, also known as the aurora borealis.’
    • ‘Colorful sky lights called auroras may be active at high latitudes and possibly into northern U.S. states and Europe.’
  • 2literary in singular The dawn.

    daybreak, break of day, crack of dawn, sunrise, first light, daylight, first thing in the morning, early morning, cockcrow
    View synonyms

Origin

Late Middle English (originally in aurora (sense 2)): from Latin, ‘dawn, goddess of the dawn’. aurora (sense 1) dates from the early 18th century.

Pronunciation

Main definitions of aurora in US English:

: aurora1Aurora2Aurora3

Aurora2

proper noun

Roman Mythology
  • Goddess of the dawn.

    Greek equivalent Eos

Pronunciation

Main definitions of aurora in US English:

: aurora1Aurora2Aurora3

Aurora3

proper noun

  • 1A city in north central Colorado, east of Denver; population 319,057 (est. 2008).

  • 2An industrial city in northeastern Illinois; population 171,782 (est. 2008).

Pronunciation