nacreous cloud


noun

a rarely seen, luminous, iridescent cloud shaped like a cirrus or altocumulus, approximately 15 miles (24 km) above the earth, and of unknown composition.
Also called mother-of-pearl cloud.

Words nearby nacreous cloud

Scientific definitions for nacreous cloud

nacreous cloud
[ nākrē-əs ]

A cloud resembling a cirrus, showing iridescent coloration when the Sun is several degrees below the horizon. These clouds appear mostly during winter in regions of high latitude.