While non-penetrative sex (or outercourse) is usually defined as excluding sexual penetration, some non-penetrative sex acts can have both non-penetrative and penetrative components and may therefore still be categorized as non-penetrative sex. Oral sex, for example, which can include oral caress of the genitalia, as well as penile penetration of the mouth or oral penetration of the vagina, may be categorized as non-penetrative sex.
Oral sex may also be considered outercourse solely because it is not vaginal or anal intercourse.
The words penetration and penetrative may be restricted to penile-vaginal penetration, and, in this way, the definition of outercourse additionally includes penetrative anal sex, with the term outercourse used to contrast the term sexual intercourse as vaginal sex. Definitions restricting the terms non-penetrative sex and outercourse to whether penile penetration has occurred, or to non-penetrative sexual acts that do not involve exchanges of potentially infectious body fluids, also exist.
