- W -

wank (off
Slang term for masturbation.

Wassermann test
A blood test for syphilis.

Western blot
A blood test for HIV antibodies.

wet dream
Slang term for nocturnal emission.

withdrawal
A method of birth control in which the male withdraws his penis from the vagina before he ejaculates; because men often secrete a small amount of fluid that often contains sperm prior to actual ejaculation, this is not a very reliable method of birth control.

Wolffian ducts
Fetal tissue that develops into the internal male reproductive structures if the fetus is genetically male.

womb
The term used for uterus by some individuals when referring to it as a container for the developing infant.

woody
Slang term for an erection.