sweedish meatball
When one is having sex with a pregnant woman, and the fetus gives you head.
While tagging the 6th month old woman, the man said, "Wow thats one great sweedish meatball."
Sweedish meatballing
The act of a male stuffing his testicles inside the vagina or anus of a sexual partner and banging the hole with said testicles. This can be done while the penis is being used in the same hole or seperate hole or balls alone.
I was banging this chick and she looked bored, so I started sweedish meatballing her butt while we screwed.