A vulgarity not to be used for sure. The word szwai is the embodiment of all vulgarities, swears and cusses into one derogatory term. This word should not be used lightly.
"That Stephanie is such a szwai!"
"Woah dude! Watch your mouth!"
A derrogative term and vulgarity. Sze Wai is the greatest insult you could ever throw at someone. Calling someone a Sze Wai is the equivalent of using all vulgarities in the English and Chinese language against them.
Chad: " My mother is such a Sze Wai,"
Stephanie: "Yo dude take that back!"