twill /twɪl/noun 2verb 1forms 3 noun2 •A pattern, characterised by diagonal ridges, created by the regular interlacing of threads of the warp and weft during weaving.Herringbone fabrics are a twill variation having the twill line reversed at regular intervals. — 2002 •A cloth or portion of cloth woven in such a pattern. verb1 •To weave (cloth, etc.) so as to produce the appearance of diagonal lines or ribs on the surface. formstwilled · twilling · twills