lenticular
len-TIK-yoo-ler
A lens-shaped cloud formed by mountain waves — smooth, dome-like, stationary even in high wind. Forms on the lee side of summits as air rides a standing wave, cooling at the crest and condensing into cloud. Often mistaken for flying saucers. Formally: altocumulus lenticularis.
Etymology
Latin lenticularis, lentil-shaped, from lens, lentil. The cloud shaped like a lens shaped like a lentil.
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