Green’s Dictionary of Slang

Jew boy n.

[not initially derog. (although note the US use of boy to address blacks)]

1. [late 18C+] a young Jewish man [SE by late 19C, though rarely used in 20C+].

2. attrib. use of sense 1.

3. [mid-19C+] a derog. term for a male Jew, irrespective of age; thus fem. Jew-girl; also attrib.