泥牛入海

níniúrùhǎi
lit. a clay ox enters the sea (idiom); fig. to disappear with no hope of returning

CEDICT

泥塑的牛一旦掉入海中，立刻瓦解。比喻一去不复返。

重編國語辭典

Homographs

泥牛入海 níniú-rùhǎi

Entry Composition

1 泥 ní
  1. mud
  2. clay
  3. paste
  4. pulp
2 牛 niú
  1. ox
  2. cow
  3. bull
  4. newton (abbr. for 牛顿 niúdùn)
  5. (slang) awesome

classifiers: 條, 頭
3 入海 rùhǎi to enter the sea (of a river, etc.)