Noun; De-fong-gal-ate. When a person or people leave without any notice whatsoever. One does not necessarily have to leave the premisis to achieve this, they may just go to bed without any warning. Is useful when its too hard to say goodbye or goodnight to whoever is present. By definition, you cannot tell someone you are going to defongalate, because it then would not be defongalation.
"I had way too much to drink last night and in the end i had to defongalate"