noctilucent cloud

noun

noc·​ti·​lu·​cent cloud ˌnäk-tə-ˈlü-sᵊnt- 

: a luminous thin usually colored cloud seen especially at twilight at a height of about 50 miles (80 kilometers)

Examples of noctilucent cloud in a Sentence

Recent Examples on the Web

Yet under the right conditions, trace amounts of water vapor can freeze onto tiny particles, creating the ice crystals that make noctilucent clouds possible. — Jamie Carter, Space.com, 10 July 2026

The rocket and its expanding exhaust plumes are being illuminated by the sun, which may produce lingering noctilucent clouds for some viewers. — Richard Tribou, The Orlando Sentinel, 9 July 2026

Paradoxically, noctilucent clouds usually form in the summer. — Margherita Bassi, Smithsonian Magazine, 30 May 2025

Water vapor is one of the three essential ingredients for noctilucent clouds. — Jamie Carter, Forbes.com, 23 May 2025

Word History

Etymology

noctilucent "luminous in the dark," from Latin noct-, nox night entry 1 + -i- -i- + lucent

First Known Use

circa 1934, in the meaning defined above

Rhymes for noctilucent cloud

• allowed
• aloud
• avowed
• endowed
• mcleod
• bowed
• browed
• cowed
• crowd
• dowd
• loud
• ploughed