Tabooed language for speakers from around the world is generally understood to refer to those lexical items and expressions considered to be unlucky, indecent, immoral, obscene, etc. because saying them would violate certain sociocultural norms; but, it is for this very reason that some speakers do indeed utter them. As for the Cantonese language, this book has investigated a set of 14 linguistic terms that its speakers have also tabooed as being inauspicious, profane, offensive, etc. This study has concluded that every tabooed lexical item has a history and development of its own; and that change of speakers' attitudes towards the types of words tabooed over time may cause changes in tabooed Cantonese lexicon which is also likely to be impacted by use of the Internet, especially among young speakers who are often at the leading edge of linguistic change.