 The two words "gam zu" ("גמ זו", meaning "this too") were combined into the single-word nickname "Gamzu" ("גמזו"), with "Ish Gamzu" then meaning "The Gamzu Man".Alternatively, Nathan ben Jehiel (in his "Arukh") describes Nachum's surname as being "Ish Gimzo", or "the man from Gimzo," based on the fact that there was a town named Gimzo in Israel at the time.This interpretation is less commonly used, possibly due to its existence in a work by a sole author outside the Talmud, whereas the Ish Gamzu explanation above exists within the Talmud itself, a more primary and respected text.