An Etymological Dictionary of Astronomy and Astrophysics

The highest clouds in the Earth’s atmosphere, at altitudes between 75 and 90 km. They resemble thin cirrus clouds with a bluish or silverish color, and are visible only during twilight.

Etymology (EN): From nocti- combining form of L. nox, → night, + L. lucent p.p. of lucere “to shine,” from lux→ light; → cloud.

Etymology (PE): Abr, → cloud, + šabtâb “noctilucent,” from šab, → night, + tâb present stem of tâbidan “to shine,” → luminous.