can be used to mean:
good (as in not bad)
bad (as in not good)
hot (as in girl)
delicious (as in food)
amazing (as in skill)
extraordinary (as in unexpected)
and so on.. it can be used for almost anything.. if you don't understand which meaning is being implied, feel free to ask the sayer of the word "fadu as in ___ or ____"
i did damn fadu, man (meaning i aced it / raped it)
how did the exam go?
man, it was too fadu (meaning it went completely over my head)
hey, do you like megan fox?
are you kidding, she's damn fadu