verb · to count backwards from a higher number to a lower one

大家一起倒数，迎接新年的到来。

verb · counting from the bottom, the back, or the end of a sequence

他的成绩在班里排倒数第一。

verb · the multiplicative inverse of a number, which when multiplied by the number results in one

2的倒数是0.5。

verb · to count from the end of a series or to be ranked from the bottom

在排队领奖的学生中，他排在倒数第三个。