''Diu'' , literally means ''fuck'', is a common profanity in Cantonese. The word ''diu'' was originally a noun meaning the penis, but it was later used as a verb. Although it is considered to be a vulgar word in Cantonese, it is used by young people in Taiwan to mean "cool" and in this context it is not censored on TV broadcasts and still generally used today.
In a manner similar to the English word ''fuck'', ''diu'' is also used to express dismay, disgrace, and disapproval in Cantonese. For example, someone may shout "''diu nei''!" at somebody when she finds the other person annoying. A common usage is the highly offensive phrase "''Diu lei loh moh''!" that literally means "fuck your mother."
The word ''diu'' is generally considered to be offensive and in its place a variety of euphemisms exist, including ''tsiu'' , ''yiu'' and ''tiu'' .
''Gau'' is a common vulgar word in Cantonese that literally means penis. For instance, the Cantonese phrase '''' that means "makes no sense" was cut to ''mo lei tau'' to avoid the sound ''gau''.
In Cantonese ''lan'' is another vulgar word that means penis. But in recent decades the character is generally considered to be equivalent to the vulgar word . A common usage is the phrase ''lan yeung'' which maybe translated into English as "Dickface".
The word ''hai'' can also mean total failure as in the phrase ''hai saai'' . The Chinese character means "to expose to the sun", but in Cantonese it is also used as a verbal particle to stress the action. To further stress the failure, sometimes the phrase ''hai gau saai'' is used . Since this phrase is highly offensive , a euphemism or ''xiehouyu'', a kind of Chinese "proverb", is sometimes used. As in a normal ''xiehouyu'', it consists of two elements: the former segment presents a scenario while the latter provides the rationale thereof. One would often only state the first part, expecting the listener to know the second. The first part is "a man and a woman having a sunbath " . Since the penis and vagina are both exposed to the sun, the second part is ''hai gau saai'' ── a pun for total failure. Since the phrase does not involve any sexual organs or reference to sex, some argue that it should not be considered as profanity. Nevertheless, "PK" is often used as an euphemism for the phrase. The written form can be seen on graffiti in Hong Kong and other places in Guangdong, China.
''Ham gaa caan''
''Ham gaa caan'' is another common curse phrase in Cantonese that literally means "may your whole family be dead". In the , it is prohibited to "use any threatening, abusive, obscene or offensive language...." However, despite the explicit prohibition of various laws, the exact definition of "obscene language" is not given in the ordinance.