The weight in grams of 9000 metres of a filament or yarn etc. The denier system was common as the standard for all continuous-filament yarns. Yarns spun from man-made staple fibre were usually designated by the count system appropriate to the method of spinning, although the fineness of individual fibres composing the spun yam was denoted by denier. The recommended system is the Tex System with the unit of decitex for filament yarns.
see also count
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A unit of weight indicating the fineness of fiber filaments and yarns, both silk and synthetic, and equal to a yarn weighting one gram per each 9000 meters; used especially in indicating the fineness of women’s hosiery
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