According to the “Answers Corporation” website, nylon was developed at both New York and London, simultaneously.

However, it has also been stated that the letters “nyl” were arbitrary and the “on” was copied from the suffixes of other fibers such as cotton and Rayon. A later publication by DuPont (Context, vol. 7, no. 2, 1978) explained that the name was originally intended to be “No-Run” (“run” meaning “unravel”), but was modified to avoid making such an unjustified claim.

Since the products were not really run-proof, the vowels were swapped to produce “nuron”, which was changed to “nilon” “to make it sound less like a nerve tonic”. For clarity in pronunciation, the “i” was changed to “y.”