(usually of very thin high-altitude clouds in the summer twilight sky) shining at night
Derived forms
noctilucence (ˌnoctiˈlucence)
noun
noctilucent in American English
(ˌnɑktəˈlusənt)
adjective
shining in the night
said esp. of high-altitude clouds (75 to 90 km or 46 to 56 mi above the earth) thatreflect twilight to the earth long after sunset or long before sunrise
Word origin
nocti- + lucent
Examples of 'noctilucent' in a sentence
noctilucent
The reason for noctilucent clouds growing more common and conspicuous could be the changing climate.
Times, Sunday Times (2006)
Noctilucent clouds used to be incredibly rare and largely seen in the polar regions.