大口環 [－－环]

Jyutping daai6 hau2 waan4
Pinyin dà kǒu huán

Definitions (CC-CANTO)
  1. name for calling people who act stupidly or without thinking (slang)
Definitions (粵典–words.hk)
  1. 名詞
    恥笑​一個​人​弱智​嘅​用​詞
    nickname for a mentally ill person or for someone perceived as stupid, literally "Sandy Bay" as a pediatric hospital is located there