通宵

tōngxiāo
  1. all night
  2. throughout the night

CEDICT

Entry Composition

1 通 tōng
  1. to go through
  2. to know well
  3. (suffix) expert
  4. to connect
  5. to communicate
  6. open
  7. to clear
  8. classifier for letters, telegrams, phone calls etc
2 宵 xiāo night