I have to agree with cutter here. I believe lisapop's definitions are somewhat confuscated, though understandably so. Consult any textile dictionary or respected fabric source, and you'll see that cutter's definition is accurate. "Ply" by definition is a yarn that is intertwined with another. 2-ply is a yarn that has two yarns intertwined with one another, resulting in greater tensile strength, durability, more volume in some cases, more girth, and a better hand, depending on the fiber. I have heard of some cashmeres being 3 or 4 ply, vs. 2-ply or what some refer to as "single ply," which really just means single yarns of cashmere. Also, lisapop's definition of worsted is a little off. "Worsting" refers to the high twists given to wool yarns in the spinning process, again resulting in greater tensile strength (most trouser and suiting wools are given an average of 25-30 twists per...inch?), a smoother hand, better resilience, more compact weaves, higher definition in patterns, and so forth. Worsted, hard milled fabrics are very, very smooth. Her trivia bit about worsted is one of the more respected hypotheses. The other is that William the Conquerer discovered the process used in this little hamlet, and felt that this fabric had "worsted" all competitors. Total speculation, of course. Sorry; don't mean in any way to be offensive or arrogant. Just trying to be as accurate as possible for the sake of clarity in understanding why certain processes are done. lisapop's mention of parallel fibers applies more to the combing of fibers, which gives them a smoothness, and also eliminates shorter "noil" ("not over an inch in length) fibers. This is more often used in terms of combed vs. carded cotton, combed being the superior choice for such things as chinos, denim, shirts, etc. Again, let me reiterate that I'm not trying in any way to denigrate lisapop's wonderful enthusiasm for textile information. We should all have such interest.