鐵竇 [铁窦]

Jyutping tit3 dau3
Pinyin tiě dòu

Definitions (CC-CANTO)
  1. a vice or gambling den located in a secure location where criminal or illegal activitites are carried out, often safe from the police as a result of connections or bribery [colloquial]
Definitions (粵典–words.hk)
  1. x