Used to avoid actually coming out and calling the person a ho to their face/behind their back. Use responsibly.
Lisa: Don't worry she is a Hydrogen Monoxide, he won't be interested.
"I feel like such a Hydrogen Monoxide, I burned 400 calories five times this weekend!!"
Marissa: You're such a hydrogen monoxide
Blonde girl: Like, what?
Blonde girl: Well...Thanks!