adj. a word describing the delicious character of a person's buttocks, based on its appearance and/or feel. It may also be seen as a play on words with the "butter" portion of the word.
Etymology: conjoined from the slang "butt", (shortened from "buttocks" meaning 'the two fleshy parts of the body posterior to the hip joints'), and "terrific" (meaning 'exceptionally good of its kind, or particularly excellent')
"Dayummm look at that girl. She is butterific!"
"Hey girl! Check out that cute boy over thurr. I just want to get up all on that butterific body."