Filling

in weaving, the threads which extend crosswise, or from side to side of the web. So called because the longitudinal or warp threads are put in position first, and are filled by the weaving process with the cross threads. The filling is also called the weft, and sometimes the woof. The word weft means literally "a thing woven," the weft threads being woven over and under the warp threads. Woof is from the Anglo-Saxon, and means literally the "on-web," that is, the web that is thrown on or across the warp threads. See Weaving; Web