Synthetic fiber (5)

I think it could be either:

nylon

rayon

'synthetic fiber' is the definition.
(I know that nylon is a type of synthetic fiber)

This is all the clue.

(Other definitions for nylon that I've seen before include "The first synthetic fibre" , "Fabric (originally from New York and London)" , "Man-made material" , "Artificial fibre" , "Polyamide" .)

I've seen this clue in the King Feature Syndicate, The New York Times and the Penny Press.

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