泪如雨下

淚如雨下
lèirúyǔxià
tears falling like rain (idiom)

CEDICT

to cry profusely

Wiktionary

哭得非常伤心，泪水如同下雨一般。形容十分伤心。《红楼梦．第一七、一八回》：「一语未终，泪如雨下。」《老残游记二编．第六回》：「环翠因提起他家旧事，未免伤心，不觉泪如雨下，掩面啜泣。」也作「泪下如雨」。

重編國語辭典

形容十分伤心

維基詞典

Entry Composition

1 泪 lèi (bound form) tears; teardrops
2 如雨 rúyǔ
  1. (literary) like rain; in large amounts
  2. like rain; in large amounts
3 下 xià
  1. down
  2. downwards
  3. below
  4. lower
  5. later
  6. next (week etc)
  7. second (of two parts)
  8. to decline
  9. to go down
  10. to arrive at (a decision, conclusion etc)
  11. measure word to show the frequency of an action