This section is from the "A Complete Dictionary of Dry Goods" book, by George S. Cole. Also available from Amazon: A complete dictionary of dry goods and history of silk, cotton, linen, wool and other fibrous substances,: Including a full explanation of the modern processes ... together with various useful tables.
Warp. The threads which are extended lengthwise in the loom, into which the weft is woven; also called chain and twist. Warp yarn is generally stronger than weft, the hardness being obtained by extra twisting of the thread. Owing to this peculiarity, it is sometimes called "twist." [See Spinning]