 Like "puk6 gaai1", the phrase can both be used to mean "prick" or to express annoyance, but many find "ham gaa caan" much more offensive than "puk gaai", since the phrase targets the listener's whole family instead of just himself.In Hong Kong, there are specific by-laws that forbid the usage of profanity in public.For instance, it is not permitted to "use obscene language … in Ocean Park", for which "an offence is liable on conviction to a fine at level 1 and to imprisonment for 1 month", while in the MTR, it was prohibited to "use any threatening, abusive, obscene or offensive language ...