The act of getting ready to put on a strap-on dildo and anally penetrate a man, or a man getting ready to be fucked in the ass by a woman wearing a strap-on.
Dave and Chuck The Freak coined the phrase "Prepare to Peg!" during one of their segments involving pegging.
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).