sub-badunkadunk sex

Sexual intercourse between the thighs, but immediately below the female posterior. This will usually result in the top surface of the penis stroking the vulva, labia, exterior opening of the vagina and, ideally, the clitoris.

There is no penetration involved, thus making the technique ideal for women who experience pain during normal intercourse; it also reduces the probability of pregnancy occurring. Please note that the probability of STD transmission is not reduced significantly, so condom use is a must for casual instances of this type of sex.

Minus the dictionary mouth:
You probably won't get pregnant, but don't count on it.
You can still easily get herpes, syphilis, gonorrhea, HPV, and AIDS... among many other STD's.

Oh yeah, to make it TRUE sub-badunkadunk sex, you gotta take her from behind (or him from behind if you are man-loving man.)