nylon: [20] English has a long history of naming fabrics after their places of origin: denim from Nîmes, for instance, muslin from Mosul, and calico from Calicut in India. It is not surprising, therefore, that the popular myth has grown up that nylon took its name from New York (ny-) and London (-lon). The truth, however, is more prosaic. Du Pont, nylon’s inventors, took the element -on (as in cotton and rayon) and simply added the arbitrary syllable nyl-. The word was coined in 1938, and its plural was in use for ‘nylon stockings’ as early as 1940.
1938, coined, according to DuPont, from random generic syllable nyl- + -on, common ending in fiber names (compare rayon), said to be ultimately from cotton. Use (in plural) for "nylon stockings" is from 1940.