Intercourse is a type of sex, but it isn't all there is to sex - by any means. By your definition, lesbians aren't having sex. Or when I've spent several hours cumming with a lover who has only used his fingers and mouth on me, it wasn't sex. Yours strikes me as a very immature and unevolved, inexperienced viewpoint.I think the reason why I don't consider oral sex as "sex" is because a girl doesn't have a chance of getting pregnant when semen is in her mouth.
Vaginal sex is pretty obvious and engaging in anal sex with a girl can get her pregnant if the semen happens to slip out of her anus and gets into the vagina.
I still go by the dictionary term for sexual intercourse...
Oh, and by the way, when you do have sex, I hope it is with women and not "girls" - 'cause a grown man having sex with girls is creepy.