(sometimes written as two words: 'green inker') A member of the green ink brigade: in British journalistic circles, these are crackpots who write letters to the editors of newspapers or to celebrities, highlighting important words and phrases by using different coloured (typically green) ink. They may also write the whole letter in a coloured ink.
A famous novelist, read the first line of a letter, which began 'Lynda, you rotten swine..' and thought: "Oh no, a greeninker!" but reading on she realised it was a friend expressing mock jealousy over a recent success of hers.
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).