Siegel (also Segal, Segali or Segel), is a German and Ashkenazi Jewish surname. Alternate spellings include Sigel, Sigl, Siegl, and others. It can be traced to 11th century Bavaria and was used by people who made wax seals for or sealed official documents (each such male being described as a Siegelbeamter). "Siegel" is also the modern German word for seal. The name ultimately derives from the Latin sigillum, meaning "seal". The Germanicized derivative of the name was given to professional seal makers and engravers.
https://en.wikipedia.org/wiki/Siegel