Something that is mediocre, but there's nothing you can do about it; when a person isn't happy with something but will be polite and accept it. The word originates from the idea that a four inch penis really isn't okay, but a normal partner's response in the moment would be a polite, "oh, it's four inches? That's fine." It's the only appropriate reaction when you've already hit the point of no return in a situation and there's no un-awkward way to back out of it.
"This date I'm on is four inches, it's fine." "The hookup situation I'm in is four inches, it's fine."
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).