Katz.

As a Jewish name generally explained as Hebrew כ״ץ (Katz), abbreviation of כֹּהֵן צֶדֶק (kohén tzédeq, literally “righteous priest”). However, the name also exists among non-Jewish Germans, where it is derived from German Katze (“cat”, cf. English Catt), from various placenames (Katzenelnbogen, Katzenberg, Katzenstein), or even from a byform of Ketzer (“heretic”). As evidenced by the Dictionary of American family names, several of these names are also found among Jews. Therefore it remains an open question to what extent the interpretation as “righteous priest” is secondary, given that it was a general practice among Ashkenazi Jews to derive or reinterpret names by phono-semantic matching (a prime example being Cohn, principally a German name from Conrad, but popularized among Jews due to the phonetic similarity with the word for “priest” mentioned above).