Sexual intercourse
Slangs for oral sex is common in Western cultures, for example: "going down on", "giving a blowjob", "giving head", or "eating out".  The technical term for oral sex is fellatio if performed on a male and cunnilingus if performed on a female. When a man performs fellatio on himself, it is called autofellatio, and autocunnilingus if a woman performs cunnilingus on herself. Few men and women are able to do this.