1. 第九十：第八十 eighties | 第九十 nineties | 第一百 hundredth...

2. 九十多岁 九十至九十九岁：Eighties 八十多岁 八十至八十九岁 | Nineties 九十多岁 九十至九十九岁 | Hundred 百岁

noun

1. the time of life between 90 and 100

Synonym: mid-nineties

2. the decade from 1990 to 1999

Synonym: 1990s

3. the decade from 1890 to 1899

Synonym: 1890s