Yarn, means any fibre, wool, silk flax, cotton, nylon, etc., spun into strands for weaving, knitting or making thread, AIR 1980 MP 69 (71). [Textile Committee Act, 1968, s. 2(g)(f)]
The fabric which is woven includes the weft which means yarn woven across the width of the fabric through the lengthwise yarn. Thus the activity of the weaving involves passing of the weft through the warp, Ess Dee Carpet Enterprises v. Union of India, AIR 1990 SC 455 (457): (1990) 1 SCC 461: (1989) Supp 2 SCR 417.
There is no particular definition of 'yarn' in the Act or the Rules or the notifications. According to the oxford Dictionary 'yarn' means any spun thread specially of kinds prepared by waving, knitting or rope-making. According to the Webster's New World Dictionary, it is defined as any fiber, as wool, silk, flax, cotton, nylon, etc., spun into strands for weaving, knitting or making thread, Aditya Mills Ltd. v. Union of India, AIR 1988 SC 2237 (2229): (1988) Supp 2 SCR 668: (1988) 4 SCC 315 (318).
Yarn is an excisable commodity normally and but for the special procedure and notification, duty thereon is leviable at the point of production and clearance for captive consumption, Collector of Central Excise v. Ashoka Mills, AIR 1990 SC 33: (1989) Supp 1 SCR 86 (89): (1989) 4 SCC 81.