Ok, this is probably the most accurate definition. Not to be confused with "yuppy", which is Young Urban Professional, a yuffy is a hippy that has betrayed their hippy origins. They are old people who now never smile, work for the establishment, and worship Satan by sacrificing your baby(JK). They are the worst people I can imagine.
Any person over 30 that shops at "Whole Foods".
damn yuffy bastards
young urban fuck up
i am a yuffy, and i am proud