低谷

dīgǔ
  1. valley
  2. trough (as opposed to peaks)
  3. fig. low point
  4. lowest ebb
  5. nadir of one's fortunes

CEDICT

Entry Composition

1 低 dī
  1. low
  2. beneath
  3. to lower (one's head)
  4. to let droop
  5. to hang down
  6. to incline
=2 谷 gǔ
  1. grain
  2. corn
=2 谷 gǔ valley