I. When you observe a female's ass through any of the following:
a. Yoga pants/Gym pants
b. Pair of Jeans
c. Swimsuit Bottoms (1 & 2 Piece)
d. Sweatpants
e. Daisy Dukes f. Any other tight-fitting, thin material
At which point you notice a lot of buldging and lumps trying to escape the underwear underneath; hence the large mass closely resembles a fully loaded diaper.
A term derived from the classic 2000s book and movie series, Diary of a Wimpy Kid. In simplest terms full diper means full send. When using Full diper you must give zero fucks. Full diper is a dangerous term due to the fact that if and when a dare is proposed and followed by the phrase full diper you have 5 hours to complete said dare. The dares should not be thought of as a punishment, instead of as a push to do something you already want to do/ have mentioned in the past. If this dare is not completed you must allow the most intoxicated member of your friend group draw an image of a male reproductive organ on your body where ever they please. Full Diper is not only a term but a life style.