noun
also cir·rhus ˈsirəs
( plural cir·ri -ˌrī)
Etymology: New Latin, from Latin cirrus curl, ringlet, bird's crest
1. : a curllike tuft : tendril
2. : any of various slender usually flexible appendages of animals: as
a. : any of the curved many-jointed arms of barnacles
b. : any of the filaments growing from the stalk and sometimes from the aboral surface of crinoids
c. : any of the tactile barbels about the mouth of many fishes
d. : any of certain tufts of hair on the legs or antennae of many insects
e. : a fused limblike group of cilia on certain protozoans
f. : the male copulatory organ of various invertebrate animals (as certain worms and mollusks)
3. : a white filmy variety of cloud usually formed in the highest cloud region at altitudes of 20,000 to 40,000 feet and normally consisting of minute ice crystals — see cloud illustration