The French Dip primarily comes in to play during heterosexual anal intercourse. The male and female partner agree on the sexual position known as doggie style. The male partner during intercourse places his thumb in his mouth and lubricates the thumb with saliva. He then slides the thumb slowly into the rectum of the female while his penis is still inside the vagina. The purpose of this exciting action is to use the rectum and lower back as a handle for more leverage while engaging in intercourse..
by david case May 08, 2006