By definition, it means "crazy" and "
pussy/
cunt".
In Cantonese, it can mean:
i. stupid
ii.
asshole
iii. close friend
i. Hey, don't be a sohai, ok? You're not the only one in this world who knows how to have an erection!
ii. You're such a fucking sohai lah! Don't you know how to eat a
pussy?
iii. Hey sohai! Long time no see!