Act in which the male reproductive organ enters the female reproductive tract (see reproductive system). Various sexual activities (foreplay) lead to physiological changes that progress to orgasm (climax) and resolution (see sexual response). If it is completed, semen passes from the male into the female's body. If conditions favour fertilization, a sperm joins with an egg, and pregnancy begins (see fertility; reproduction); contraception can prevent this. Intercourse with an unwilling female is rape. See also reproductive behaviour; sexuality, human; sexually transmitted disease.
This entry comes from Encyclopædia Britannica Concise.For the full entry on sexual intercourse, visit Britannica.com.
What made you look up sexual intercourse? Please tell us what you were reading, watching or discussing that led you here.
Take our visual vocab quiz
A quick quiz about stuff worth knowing
The commonly misspelled words quiz
The Vocab Quiz Game for iPhone & iPad
"Incredibly fun and addictive. And informative!" User Review, iTunes