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

Etymology

Origin of noctilucent

First recorded in 1885–90; nocti- + lucent

Example Sentences

Strahan also said the excess water vapor could enhance the formation of special noctilucent clouds, which appear as shimmering, ghostlike wisps in the night sky.

From Washington Post • Aug. 5, 2022

She said the frequency of noctilucent clouds in the past few days has been higher than ever observed in at least 15 years of observations by the AIM mission.

From Washington Post • Jul. 2, 2022

Alan Tough spotted these rare noctilucent clouds in Elgin, Scotland.

From BBC • Jul. 30, 2011

It is thought that the increase in brightness and frequency of noctilucent clouds over past decades may be linked to global warming.

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 Savage, Arthur Dekker