- 数九寒天 shǔjiǔhántiān coldest days of the yearthe coldest time of winter, specifically the nine periods of nine days each following the winter solstice
- 数九天 shǔjiǔtiān the coldest time of winterThe period of eighty-one days following the winter solstice, traditionally divided into nine sets of nine days each and considered the coldest time of the year.