Pronunciation: (sir'us), [key]
—pl. cir•rus for 1, cir•riPronunciation: (sir'ī) [key] for 2, 3.
a. a cloud of a class characterized by thin white filaments or narrow bands and a composition of ice crystals: of high altitude, ab. 20,000–40,000 ft. (6000–12,000 m).
b. a cirriform cloud.
2. Bot.a tendril.
a. a filament or slender appendage serving as a foot, tentacle, barbel, etc.
b. the male copulatory organ of flatworms and various other invertebrates.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.