Vulgar
Used in Hong Kong
Pronunciation: "on-gau" ("on" in English, "9" in Cantonese)
Meaning: stupid, thinking stupid
More: [on99]
> Chief Exceutive Mr.Tung: If China is good, Hong Kong will be good. When Hong Kong is good, we are good too.
> Citizen A: He's on9.
> Citizen B: He's on99.