杜口

dùkǒu
to remain silent

CEDICT

  1. (literary) to remain silent
  2. to remain silent

Wiktionary

闭口不言。

重編國語辭典

Entry Composition

1 杜 dù
  1. birchleaf pear (tree)
  2. to stop
  3. to prevent
  4. to restrict
2 口 kǒu
  1. mouth
  2. classifier for things with mouths (people, domestic animals, cannons, wells etc)
  3. classifier for bites or mouthfuls

Containing this entry

杜口裹足 dùkǒuguǒzú too frightened to move or speak

Related entries

无言 wúyán
  1. to remain silent
  2. to have nothing to say
无语 wúyǔ
  1. to remain silent
  2. to have nothing to say
  3. (coll.) speechless
  4. dumbfounded
我無語了。

Words fail me.

Source: Tatoeba