1. Black man having sex with a white woman.
2. White woman having a relationship with a black man.
Literally translated, it means 'nigger in the ass'.
This phrase is comprised of the word nignog which is slang originating in Maine for 'nigger' and 'kazoo' being slang for ass. In this instance the ass is that of a white woman. This phrase has been heard in parts of Rhode Island, Massachusetts, Connecticut, New Hampshire, Maryland, Nevada, and Florida.
Did you see that girl? Looks like she's got a nignog in the kazoo!