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

“We are near the peak of the noctilucent cloud season, and even in the absence of extraordinary events, they can appear over the northern continental U.S.”

From Washington Post • Jul. 2, 2022

Before sunrise on Friday, they tweeted photos of the “most vivid displays of noctilucent clouds” claimed to be seen in decades in the area.

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

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

Like noctilucent clouds high above the cirrus belt.

From The Scarlet Lake Mystery by Goodwin, Harold L. (Harold Leland)