洪水猛獸 [－－－兽]

Jyutping hung4 seoi2 maang5 sau3
Pinyin hóng shuǐ měng shòu

Definitions (CC-CEDICT)
  1. lit. severe floods and fierce beasts (idiom)
  2. fig. great scourges
  3. extremely dangerous or threatening things
Definitions (粵典–words.hk)
  1. 名詞
    比喻​為​兇猛​、​險​惡​嘅​事物
    extremely dangerous or threatening things; literally: flood and fierce beasts
Definitions (Wiktionary)
  1. phrase, idiomatic
    enormous disasters; something that causes enormous damage
Definitions (Kaifangcidian)
  1. （沒有對應漢語詞彙）