cirrus

Etymology

From Latin cirrus (“curl”).

noun

1. (botany) A tendril.
2. (zoology) A thin tendril-like appendage.
3. (meteorology) A principal high-level cloud type characterised by white, delicate filaments or wisps, of white (or mostly white) patches, or of narrow bands, found at an altitude of above 7000 metres.
   He looked at the sky and saw the white cumulus built like friendly piles of ice cream and high above where the thin feathers of the cirrus against the high September sky. 1952, Ernest Hemingway, The old man and the sea, Harper Perennial classics, published 2014, page 282