The seventeenth item in a series is the one that you count as number seventeen.
例句
She gave birth to Annabel just after her seventeenth birthday.她 17 岁生日刚过便生下了安娜贝尔。
FRACTION
十七分之一
A seventeenth is one of seventeen equal parts of something.
英汉词典释义
pron.
第十七(个)
Girls used to put their hair up on their seventeenth birthdays.过去的姑娘17岁生日时就把头发束起来。It happened on January the seventeenth.事情发生在1月17日。These clubs began as coffeehouses in the seventeenth century.这些夜总会在17世纪时原来是咖啡馆。