Meteorology. A form of cloud, generally at a high elevation, presenting the appearance of diverging filaments or wisps, often resembling a curl or…

curl-crested, curl-faced, curl-headed adjs.; curl-tuft; curl-cloth n. a kind of woollen cloth with a curly surface. curl-cloud n. = cirrus, n.1 4.

attributive and in other combinations, as cirrus-cloud, cirrus-flecked adj. (sense 4).