通宵达旦 tōng xiāo dá dàn

DEFINITIONS

  1. overnight until daybreak (idiom); all night long
  2. day and night

CHARACTERS

通 tōng
HSK 4
pass through, common, communicate
宵 xiāo
HSK 6
night, evening, dark
达 dá
HSK 5
arrive at, reach; intelligent; smooth, slippery
旦 dàn
HSK 5
dawn; morning; day