A person whom only washes their hands after using the restroom in the visible presence of others. If it "appears" that nobody is present (i.e. somebody is in the stall, or they didn't notice someone was in the room with them), or nobody is actually in the restroom with them, they will leave after using the restroom and not wash their hands.
Christa is a party washer. She only washes her hands in public bathrooms where other people may see her. But not if she thinks she's alone.
When you have to pee in a movie but don’t want to miss anything, and must do the following mental equation: will the amount I have to pee cause enough discomfort to diminish my attention capacity for the remainder of the movie to an extent which is greater than the amount of the movie I would miss by making a mad dash to the restroom.
I saw Satantango last night, wonderful film but by the 5th hour I had to start doing pee calculus.
Short-hand for the word floccinaucinihilipilification, meaning the estimation of something as valueless (encountered mainly as an example of one of the longest words in the English language).