Erroneously cirrhus. [L. cirrus curl, fringe, etc.]
ǁ 1. lit. A curl-like tuft, fringe or filament.
1708. Phillips, Cirrus, a Tuft or Lock of Hair curled.
2. Bot. A tendril: see quots. 1845, 1870.
1708. Phillips, Cirri are also taken for these fine Strings, or Hairs, by which some Plants fasten themselves; in order to their Support in creeping along; as Ivy, &c.
1845. Lindley, Sch. Bot., i. (1858), To The midrib [of the leaf] is lengthened, and acquires the power of twining round small bodies … it then has the name of cirrhus or tendril.
1870. Bentley, Bot., 103. Tendril or Cirrhus … is applied to a thread-like leafless branch, which is twisted in a spiral direction.
3. Zool. A slender or filamentary process or appendage, as the fleshy barbel or beard of some fishes, the feet of Cirripedes, the lateral processes on the arms of Brachiopoda, etc.
1753. Chambers, Cycl. Supp., Cirrus, certain oblong and soft appendiculæ hanging from the under jaw of fishes.
1828. Stark, Elem. Nat. Hist., II. 126. Tubinicella, Lam. Body inclosed in a shell, with the cirri small, setaceous, and unequal.
1834. Sir C. Bell, Hand, 147. Fishes have cirri which hang from their mouth.
1834. McMurtrie, Cuvier’s Anim. Kingd., 274. [In barnacles] the mouth is at the bottom and the cirri near the orifice.
1877. Huxley, Anat. Inv. Anim., v. 231. In some somites this appendage is a cirrus.
4. Meteor. A form of cloud, generally at a high elevation, presenting the appearance of diverging filaments or wisps, often resembling a curl or lock of hair or wool. Particular varieties are known as Cat’s or Mare’s Tails. See CIRRO- 2.
1803. L. Howard, Modif. Clouds (1865), 2–3. It may be allowable to introduce a Methodical nomenclature, applicable … to the Modifications of Cloud.…
Cirrus.… Parallel, flexuous, or diverging fibres, extensible by increase in any or in all directions.
1815. T. Forster, Res. Atmosph. Phenom., iv. § 3. 143. When the cirrus is seen in detached tufts, called Mare’s Tails, it may be regarded as a sign of wind.
1866. Cornh. Mag., Nov., 565. The moon … disc-hid In a gossamer veil of white-cirrhus.
1874. Hartwig, Aerial W., xi. 158. The cirrus or curl-cloud has its seat in the higher regions of the atmosphere.
5. attrib. and in Comb., as cirrus-cloud, -flecked adj. (sense 4); cirrus-bag, ‘the sheath containing the cirrus of trematode and other worms.’
1864. R. F. Burton, Dahome, 17. The cirrus-flecked nocturnal sky.
1878. Huxley, Physiogr., 42. The cirrus clouds are always lofty, sometimes as much as ten miles above the surface of the earth.
