acronym - public display of intercourse. usually occurs at school, during a movie, when the teacher has the lights turned off and the students are allowed to lie about on the floor.
"Dude, I've been scarred for life. I saw Tony and Aimee doing PDI during that U.S. history movie."
PDIP (Partai Demokrasi Indonesia Perjuangan) is an Indonesian political party, and the party of the current President of Indonesia, Joko Widodo. The PDI-P is currently led by Megawati Soekarnoputri, Indonesia's Fifth President and the daughter of Indonesia's First President Soekarno.
A game in which whenever you see a car with only one headlight, whoever isn't quick enough to call "pdiddle" first has to take off one item of clothing.
*car passes with one headlight* John calls "PDIDDLE!!" and Sarah and Matt both take off their shirts.