Dreyfuss is a surname believe to have originated in the German city of Trier. The Latin name for the city was "Treveris," which developed into its current pronunciation through sound shifts of /t/>/d/ and /f/>/v/. The spelling variants tend to correspond to the country the family was living in at the time the spelling was standardized. The use of one "s" tends to be more common among people of French origin, while the the use of two "s"s tends to be found among those of German descent (stemming from the use of the Eszett).