A BBC dream is a dream had by white women in which they shout out "give me that big black cock now!!!" This can be very embarrassing and awkward if the lady is sleeping with her husband or boyfriend. The morning conversation usually goes something like this. Do I satisfy you, honey? Of course, sweetie! (crosses fingers) So what was that you were shouting in the night? Don't worry honey, that was just a big black cock dream. All girls have them.