köken: Coined by Peyo, probably from German Strumpf (“stocking, sock”), which is not semantically related, but peculiar and “funny sounding” to the French ear because of the unfamiliar combinations of consonants. See also smurf.
Alteration of French schtroumpf, itself probably from German Strumpf (“stocking”). Whether the form was coined at random by the German translator or whether it was influenced by the surname below or perhaps by some other word, appears to be unknown.