noctilucent

American  

[nok-tuh-loo-suhnt] / ˌnɒk təˈlu sənt /

adjective

Meteorology.

1. (of high-altitude clouds) visible during the short night of the summer.

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noctilucent British  

/ ˌnɒktɪˈluːsənt /

adjective

1. shining at night, usu. of very thin high altitude clouds observable in the summer twilight sky

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noctilucent Scientific  

/ nŏk′tə-lo̅o̅′sənt /

1. Luminous at night. The term is used especially to describe certain high atmospheric cloud formations visible during summer nights at high latitudes.

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Other Word Forms

• noctilucence
  noun

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Etymology

Origin of noctilucent

First recorded in 1885–90; nocti- + lucent

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Example Sentences

See Examples For:

noctilucent

The records contain mentions of major aurora events and some of the first recorded observations of noctilucent clouds which are such a feature of clear summer nights in the north of Ireland.

From BBC ● Jul. 13, 2025

Previously, researchers found water vapor released from these missions can lead to the formation of noctilucent clouds.

From Washington Post ● Jul. 2, 2022

“Folks in the northern U.S. and Canada should absolutely be on the lookout for noctilucent clouds over the long weekend,” Cora Randall, a professor at the University of Colorado Boulder, said in an email.

From Washington Post ● Jul. 2, 2022

It was a close call between John Rowlands' study of noctilucent clouds, and an entry by art gallery owner Shane Record from Kent.

From BBC ● Apr. 24, 2010

Down, down for dim countless minutes, through the thin ionization of E, past the lowest ranges of auroras and noctilucent clouds and below the ozone layer.

From Fly By Night by Arthur Dekker Savage

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