Green’s Dictionary of Slang

the penis.

1926		Odum & Johnson Negro Workaday Songs 175: Wring Jing had a little ding.
1952		in G. Legman Limerick (1953) 278: It made his ding bounce, / And he caught every ounce / Of his magical spraying of sexus.
1967		N. Mailer Why Are We in Vietnam? (1970) 142: Coitus all interruptus with electric coils of gas in your bowel, pain in your balls, and hate in your ding.