warp

The warp is the set of parallel threads held under tension on a loom, running the length of the fabric from the weaver's perspective. These are the stationary threads, stretched tight between the beam at the back of the loom and the cloth beam at the front. The weft (or woof) threads are then woven across them, over and under, to form the finished cloth. In any woven fabric, the warp carries the strain of the weaving process and defines the fabric's length and straightness.

Warp threads are typically stronger and more tightly twisted than weft threads because they must withstand constant tension and the impact of the shuttle or gripper carrying the weft back and forth. Thread count in the warp direction (measured in threads per inch) directly affects the fabric's stiffness, durability, and surface finish. A finer warp with higher thread count produces a smoother, tighter cloth; a coarser warp with lower count yields a looser drape.

Preparation and common problems

Before weaving begins, the warp must be wound onto a beam in the correct sequence and tension. This process, called warping, requires careful attention to fiber type and tension uniformity. Uneven tension across the width of the loom causes skew (diagonal distortion) in the finished fabric. Broken warp threads during weaving halt production and must be repaired or the loom reset. Warp breakage is often traced to weak spots in the yarn, excessive tension, or friction from worn guides and healds.

The name 'warp' derives from the Old English 'weorpan', meaning to throw or fling; in Old Norse usage it referred to threads thrown or cast on the loom. This etymology reflects the physical act of laying out lengthwise threads before interlacing the weft. In modern textile mills, the distinction between warp and weft is absolute and defines the direction of any pattern or finish applied to the fabric.