Well, it kinda depends on whom you ask:
- Sex, Etc. says a hookup happens when two people are sexual with each other.
- Students at Skidmore College define "hooking up" as anything from making out to oral sex to sexual intercourse.
- Jessica Rozler, who wrote The Hookup Handbook, defines "hooking up" as anything more than a kiss.
- Most Teen Vogue readers say that only kissing and touching count as hookups.
- Geek.com says that "hooking up" is when you attach your iPad to a 3G network. (I'm not sure why we bothered to ask them.)
There's one thing everybody agrees on, though: hooking up happens outside of relationships. There's no commitment involved, meaning that if you hook up, the other person might have no expectations of hooking up with you again - and many hookups stay one-night stands.
If you've got your own definition of "hookup," share it here!