A sheath, usually made of latex, designed to cover the penis during sexual intercourse to help prevent pregnancy and reduce the risk of sexually transmitted diseases, including HIV
rubber (usually) sheath worn over the penis to prevent pregnancy or sexually transmitted disease during sexual intercourse.
a barrier method of birth control. There are both male and female condoms. The male condom is a sheath placed over an erect penis before sex that prevents pregnancy by blocking the passage of sperm. A female condom also is a sheath, but is inserted into the vagina to block the passage of sperm.