Green’s Dictionary of Slang

(US) a Jewish person.

1975		in National Lampoon (Jan. 1976) 24: UN Resolution Says Nickelnoses [Jews] discriminate Against Tentheads [Arabs] [HDAS].
1983		Beckwith & Knox Delta Force 151: He then advised me I was a nickel nose. Other miserly expletives, many of which I’d never heard before, filled the room.