rayon (n.)
1924, chosen by National Retail Dry Goods Association of America, probably from French rayon "beam of light, ray," from rai (see ray (n.1)), which also was used in Middle English as a name for a type of cloth. So called because it is shiny. A more marketable alternative than the original patented name, artificial silk (1884), or the intervening attempt, Glos, which was "killed by ridicule" ["Draper's Record," June 14, 1924].