Katzenellenbogen is an Ashkenazi surname derived from the name of the former County of Katzenelnbogen, a powerful medieval state of the German Empire (see also Katzenelnbogen Castle and town). Protection money paid by the Ashkenazi was a source of income for the principality. Different spellings of the toponym and surname include Katzenelenbogen and Katznelbogen, with further derivative forms and spellings of the surname like Katsenelenbogen, Catzenellenbogen, Katzin, Katz, Elbogen/Ellenbogen and Bogen.
Katzeneleson, Kazenelson, Kaznelson are further variations of the name by addition of the ending -son, 'son (of)'.