Definitions by Professor LA

basement business 

The first known use was in the movie Manchester by the Sea. When asked if the nephew was sleeping with a specific girls he answered, "its just basement business", when asked more specifics he simply said I'm working on it.

So basement business is teenage monkey business usually of a sexual nature.

Have you and she had sex even though her mother is home? No it's just {basement business].

basement business by Professor LA July 12, 2017