What is Tencel®?: Tencel is the most famous trademarked name for the fiber lyocell. Lyocell is the newest fiber around, the answer for contemporary consumers who want the comfort and luxury of a natural fiber with the practicality of a man-made fiber. Natural in origin, lyocell is breathable, absorbent, and comfortable to wear. Read more about lyocell and other fibers in our 'Fabric Guide' under Customer Service.