Definition from the region of Northern California.
Many definitions are correct especially being a skater/surfer term but where I grew up late 90's to 2000's it meant:
1) Dirty hippie
kid who wore really baggy clothing and was always
stoned.
2) Smelly hippie (usually white
kid) with dreadlocks who didn't do anything but skate and smoke. Most likely on the lower end of the social ladder.
3) A straight
bum who was burnt out. An offensive word if you had your shit together.