Lyocell is a form of rayon. It consists of cellulose fibre, made from dissolving pulp and then reconstituting it by dry jet-wet spinning. The fibre is used to make textiles for clothing and other purposes. Unlike rayon made by the viscose process, lyocell production does not use harmful carbon sulfide, which is toxic to workers and the environment. As of 2018, the lyocell process is more expensive than the more common viscose process for making rayon.
"Lyocell" has become a genericized trademark, used to refer to the lyocell process for making cellulose fibers. The U.S. Federal Trade Commission defines lyocell as a fibre "composed of cellulose precipitated from an organic solution in which no substitution of the hydroxyl groups takes place and no chemical intermediates are formed". It classifies the fibre as a sub-category of rayon.