The following glossary is adapted from the glossary provided by Planned Parenthood at https://www.plannedparenthood.org/learn/glossary.
Egg: The reproductive cell in women; the largest cell in the human body.
Ejaculation: The moment when semen spurts out of the opening of the urethra in the glans of the penis.
Emergency contraception: Hormonal birth control pills used to prevent pregnancy after unprotected vaginal intercourse. Must be started within 120 hours (five days) of intercourse. IUDs can also be used as emergency contraception, if inserted within five days of unprotected intercourse to prevent pregnancy.
Endometriosis: The growth of endometrial tissue outside of the uterus, causing pain, especially before and during menstruation.
Endometrium: The lining of the uterus that develops every month in order to nourish a fertilized egg. The lining is shed during menstruation if there is no implantation of a fertilized egg.
Endorphin: A hormone that suppresses pain.
Epididymis: The tube leading from the testis to the vas deferens in which sperm are stored before ejaculation. It is tightly coiled on top of and behind the testis. The plural of epididymis is epididymides.
Epididymitis: An inflammation of the epididymis.
Erectile dysfunction: The inability to become erect or maintain an erection with a partner.
Erectile tissue: Spongy tissue in the body that stiffens when filled with blood. See “vasocongestion.”
Erection: A “hard” penis when it’s becomes full of blood and stiffens. See “vasocongestion.”
Estrogen: A hormone commonly made in a woman’s ovaries. Estrogen’s major feminizing effects are seen during puberty, menstruation, and pregnancy.
Estrus: The cyclic period of fertility and sexual receptivity in sub-primate female animals (vertebrates).
External sex and reproductive organs: The sex organs and structures on the outside of the body that are primarily used during sexual activity. These include the vulva in a woman and the penis and scrotum in a man.