Following the initial berner (pre boner) and after experiencing climax with a boner, the afterberner is what's left of your penis after sex.
Usually awkward and unwanted the afterberner will leave it's owners with a slightly larger, limp and soft berner.
"Hey Danny tuck that afterberner in man you want your mom to see that?"
"Maybe"
When forcefully and repeatedly thrustyour penis into the tailpipe of an ex's car.
Garret: Hey man, did I tell you about that time that my ex cheated on me, so I gave her Honda Civic a Redneck Afterburner?!
Jack: Oh my god, that's hilarious, I did that to my ex after she gave me a windy tuna!
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).