Discovering (to your embarrassment) that a term thought to have a political meaning also has a sexual one. When this occurs in casual conversation the situation is referred to commonly in other awkward conversations.
person1: Have you heard about the teabagging party put on by the teabag association to protest the administration's value added tax.
person2: Dude, that's kind of a lude sexual act, you may not want to advertise it as a teabagging party - check out UD dot com next time before you print posters for the office.
Doug has gotten in the habit of doing a "discover teabagging" on UD before discussing weird political events, since Mary slapped him last month.