綠頭巾 [绿头－]

Jyutping luk6 tau4 gan1
Pinyin lǜ tóu jīn

Definitions (CC-CEDICT)
  1. green turban (figuratively, a symbol of being a cuckold)
Definitions (Wiktionary)
  1. noun, dated, idiomatic
    A symbol that the wearer has been made a cuckold.
  2. noun, literally
    green headscarf
Definitions (Kaifangcidian)
  1. （沒有對應漢語詞彙）