front flossing

The act of only flossing the teeth that people will see. People who engage in this behavior are often suspect of not keeping other areas as clean as they should be.

Peter: I just came back from the dentist and she was pissed at me.
Mary: Why's that? You seem to take of your teeth. Your smile looks clean.
Peter: That's it. She knows I am only front flossing. It was embarrassing.
Mary: It should be! Take an extra minute out of your day! I bet you only wash your hands when people are around.
Peter: Sometimes I only use water when soap is available. Even after a poo. I'm a mess!

Front flossing

When a woman’s underwear, specifically a thong, is pulled up in the front to cut between her labia majora.

Her hot pink thong was pulled up so far she was front flossing