thirty
/ˈθɜːtɪ/cardinal number
(pl. -ies)
1- the number equivalent to the product of three and ten; ten less than forty;30三十; 三十个：
thirty or forty years ago
三四十年前
thirty were hurt
有30人受伤
thirty of her school friends.
她的30位校友。
(Roman numeral: xxx or XXX. 罗马数字：xxx或XXX.)
1.1
- (thirties) the numbers from thirty to thirty-nine, especially the years of a century or of a person's life.三十几; 三十年代; 三十几岁：
a woman in her thirties
一个三十多岁的女人
she was a famous actress in the thirties.
她是30年代的著名演员。
1.2
- thirty years old三十岁：
I've got a long way to go before I'm thirty.
我离30岁还早着呢。
1.3
- thirty miles an hour时速三十英里：
doing about thirty.
开车时速约30英里。
1.4
- a size of garment or other merchandise denoted by thirty（衣服等商品的）三十号。
派生词
thirtieth
ordinal numberthirtyfold
adjective & adverb词源
Old English thrītig （see THREE， -TY2）. The spelling with initial thi-is recorded in literature in the 15th cent., and has been the prevalent form since the 16th cent.