Twill – Types of textile weave with a pattern of diagonal parallel ribs (in contrast with a satin and plain weave). This is done by passing the weft thread over one or more warp threads and then under two or more warp threads and so on, with a “step” or offset between rows to create the characteristic diagonal pattern. Because of this structure, twills generally drape well.

Soil and stains are less noticeable on the uneven surface of twills than on smooth surfaces, such as plain weaves. Thus, twills are often used for sturdy work clothing.

The fewer inter-lacings in twills allow the yarns to move more freely, and thus they are softer, more pliable, and drape better than plain-weave textiles. Twills also recover from wrinkles better than plain-weave fabrics do. When there are fewer inter-lacings, yarns can be packed closer together to produce high-count fabrics. In twills and higher counts, the fabric is more durable and air- and water-resistant.

There are even-sided twills and warp-faced twills. Even-sided twills include foulard or surah, herringbone, houndstooth, serge, sharkskin, and twill flannel. Warp-faced twills include cavalry twill, chino, covert, denim, drill, fancy twill, gabardine, and lining twill.