Coitus

Sexual intercourse, or coitus or copulation, is principally the insertion and thrusting of the penis, usually when erect, into the vagina for sexual pleasure, reproduction, or both. This is also known as vaginal intercourse or vaginal sex. Other forms of penetrative sexual intercourse include anal sex (penetration of the anus by the penis), oral sex (penetration of the mouth by the penis or oral penetration of the female genitalia), fingering (sexual penetration by the fingers), and penetration by use of a dildo (especially a strap-on dildo). These activities involve physical intimacy between two or more individuals and are usually used among humans solely for physical or emotional pleasure and commonly contribute to human bonding.

A variety of views concern what constitutes sexual intercourse or other sexual activity, which can also impact views on sexual health. Although the term sexual intercourse, particularly the variant coitus, generally denotes penile–vaginal penetration and the possibility of creating offspring, it also commonly denotes penetrative oral sex and penile–anal sex, particularly the latter. It is usually defined by sexual penetration, while non-penetrative sex acts, such as non-penetrative forms of cunnilingus or mutual masturbation, have been termed outercourse. Non-penetrative sex acts, however, may additionally be considered sexual intercourse. The term sex, often a shorthand for sexual intercourse, can mean any form of sexual activity. Because people can be at risk of contracting sexually transmitted infections during sexual activities, though the transmission risk is significantly reduced during non-penetrative sex,safe sex practices are advised.

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