motzer, n. — Green’s Dictionary of Slang

motzer n.

also matzo, motza, motzey, motzie, motzy

[Heb. matze, unleavened bread, trad. eaten at the Jewish festival of Passover]

1. (US) a Jew.

1894		in R.F. Outcault Yellow Kid 26: Issy Silberman may be a motzer. But de day will come when [he] is a millionaire banker.
1900		E.H. Babbitt ‘College Words and Phrases’ in DN II:i 46: Motzy, n. A Jew or Jewess.
1911		S. Ford Torchy 110: I spots Abey Winowski on the fringe of the push. [...] ‘Hello, Motzie!’ says I.
1983		Maledicta VII 23: Jews were called […] matzo, motza, motzer, and rarely motzey.